Players come to Null-sec for the large-scale fights and owning space. Ideally, these fights happen multiple times a day. While that was the case in the last war in the North, Null-sec has become quiet for many alliances of late. Part of the issue is likely fatigue of both the player base and FCs, and frustration with the boring sovereignty grind. Regardless, everyone has been trying to 'create content' and use up the spare time: many are ratting, but some have tried to go out in small roaming gangs. Unfortunately that brings them back to their previous problem: space with a whole lot of nothing. God forbid some players actually manage to organize a small gang, they then have to look at the prospect of going over 20 jumps away just to see someone they're allowed to shoot. Just as the empty space is a deterrent to roaming gangs, it is a deterrent to enemy gangs. This creates a sense of security, and consequently players have no motivation to go out roaming (aside from sheer boredom). Clearly things aren't working as intended...
Nulli Secunda is currently living in Immensea, along with Pangu alliance. A lot of the systems in the region are still Against All Authorities space or one of their allies, but any player would be hard pressed to find any of them. In fact, in the entire region anyone would have to work hard finding anyone else. Immensea contains 84 systems and 17 conquerable stations. Given the total number of players for these alliances of around 2700, and at a 'good' activity level of 10%, that would mean at any one time there are around 270 active players in the region.
In a region with 84 systems there is an average density of 3.5 players per system. That doesn't look good for Null-sec. Of course, that average is very strongly skewed by the high concentration of those players in a few systems. Bringing up Dotlan makes it obvious that the players are concentrated in three or four systems. Even more disturbing, in the last 24 hours, there have been a whopping 5 systems with more than ten PvP ship kills, and over 56 systems without a single kill.
If only this trend was only apparent in this area of space and an exception! Unfortunately, much of Null-sec paints a similar picture. One can easily travel all the way from the North to the South without encountering a single neutral ship in 0.0 space. Even the 'denser' areas of null, arguably those of the HBC and the CFC, with leaders who actively encourage players to use their space, are not much better. The only way around this issue is the widespread use of jump bridges and titan bridges, the former requiring sovereignty (which tends to increase the problem rather than reduce it) and the latter requiring a cyno ship in a destination system anyway.
Recently, there has been a lot of talk about 'farms and fields' type systems that would help resolve this problem. Potentially such a system would bring out more carebears and more associated roaming gangs. Unfortunately, due to the spacing of the systems, it is unlikely to solve this issue (serious motivation is needed to go 30ish systems to find a fight). While it will certainly revolutionize Null-sec dynamics and provide much-needed rewards for the grunts of alliances, it won't help fill out Null any more than it is now.
One common solution that's been floating around is increasing the value of Null-sec systems. Currently, there is too much of a disparity between systems: some have stations and some don't (meaning alliances are almost guaranteed to NOT stage from such a system), some have -1 sec status and some have -0.1 (meaning ratting is much more profitable in one than another). Some are also inherently safer than others by being dead-end systems. If the values of systems are more homogenous but the actual value of systems increase, it may reduce the current 'island' system currently seen. It is unlikely that homogeneity is the answer: some variation can make space a bit more interesting, and it does actually cause some conflict every now and then.
The crux of the issue then is that alliances own too many systems to use them all. A simple explanation to the issue could be that there are simply too few players in Null (or too many Null-sec systems). Part of this may be due to the attraction of Null in the first place, or that there are simply not enough players currently engaged in EVE to populate the area. Even if alliances owned less territory, there would still be the issue of actually populating the systems in question. Neither of those two issues can easily be fixed, so they'll be ignored for now.
Some might argue that the large coalitions that now exist prohibit new alliances from entering the area. While that is a valid point, it doesn't necessarily mean that the total number of players in Null would be significantly higher if it wasn't the case. The only new alliances that would increase the total player numbers would be those already existing High/Low-sec that decide to make the move, and they are a rare breed.
SLEEPING NEXT TO A DRAGON
That is really what this issue boils down to: to get easier PvP, alliances need to live closer to each other. Bridges of various kinds make the effective distance between coalitions shorter than they actually are, meaning that in real space alliances need to be further away from their enemies and by association worsening the problem. CCP needs to increase the relative density of Null-sec systems, but that's not going to happen given that enemy coalitions are only a few 'effective jumps' away from each other thanks to titan bridges.
Here is a hypothesis: what if a 10000 man alliance only needed 5 systems to meet all its needs, and a 2000 man alliance only needed one? Judging by Dotlan, this is already rather close to being the case: Nulli Secunda for example, a 2000 man alliance, only actively uses two or three systems. Continuing the hypothesis: what if instead of being 3-4 titan jumps away from each other, the alliances were 1 bridge away? And that said bridge had a lower range than it did now? So that while the effective separation of opponents was 1 bridge, it was only 10 jumps away (rather than the 20ish now currently observed per bridge)? Wouldn't it be glorious if two opposing alliances could just ship up and go 10 jumps away knowing they'd find enemies?
The obvious issue that arises with such a hypothesis is :"why wouldn't the larger entity just kick the other out? And that leads us to the previous issues". Clearly, sovereignty needs a revamp. There are a number of possibilities to address this issue: having sovereignty linked to player activity of sorts (so that a 10000 man alliance has trouble owning more than 5 for example), or to have detrimental costs associated with larger sovereignty. If the larger entity could take the smaller above alliance's sovereignty from a strategic standpoint, but it would risk losing one due to lack of activity or increased costs, it would focus on pushing it out by attrition. Effectively it would not take sovereignty but attempt to push the enemy alliance out through shitloads of PvP. Of course, to compensate for the added risk brought on by having an enemy alliance next door, the rewards from living in null would have to increase proportionally, close to the levels achieved in wormhole space (which would be justified: just like w-space, players would have to assume there are always potential enemies around).
At the end of the day, there is just too much space for the current player base. Without an effectively higher player density, Null will remain (for the most part) very quiet. Given the prospective increase in EVE subscriptions, it would take years to even double the current Null-sec population, which would not even come close to making it more populated (and that still leaves the large distances involved, the additional players could just join current alliances that wouldn't increase the spread of the populations).
Applying Occam's Razor to the problem: there are two variables that affect the average player density in Null; the number of active players, and the number of total systems. While CCP can always aim to increase the number of active players (and a farms and fields system would go a long way towards that objective), their best efforts are unlikely to increase the player base by the three- or fourfold necessary to create a 'busy' 0.0 space. CCP HAS to reduce the number of systems in Null-sec. There are many ways they could do it: give players ample warning, keeping the systems with stations (where the most player-owned assets would be), refunding assets in other systems, eliminate least-busy/used systems first... It just needs to be done. CCP took the precautionary approach with the creation of a large number of 0.0 systems, but this has ended up creating a very quiet area of space that was supposed to be the most exciting with constant PvP.
Living a few jumps from a number of potentially dangerous alliances? Yes please. CCP, make it happen.