Disclaimer:
Let me make it clear that what I'm posting is a personal opinion and in no way reflects on the opinion of my Corp. I've had no discussions with them at all on this topic in fact.
After reading this thread through several times today at work, it seems to me that the majority of the discussion has been about the "Max" side of how these changes effect the game, Corps. and alliances, not about the "Min" side: i.e., what are the lowest barriers to entry for these changes to be beneficial to a Corps.
I think it's impossible to read the whole devblog about these changes and not assume the devs want to create more opportunity for more Corps. while reducing the value of alliances. By opportunity, I don't just mean Beta outpost ownership but also more PvP and more economic activity, which will benefit all the players and make the game more attractive to new ones.
The discussion, so far, has primarily focused on how to make an outpost "safe" for the owner and allow them to get the maximum benefit 24/7. The "solution" to this dilemma has been mostly stated as increasing the size of ones Corp. with recruitment or the absorption of previously allied Corps. Frankly, I think the whole Max/safe line of reasoning is both a bit carebear and counter to what the devs intend and what's best for the games growth.
So let's look at the other side of the equation.
There are currently 15 Beta outposts. Considering the cost and attention required to maintain the stability of even one, it would be unlikely that even the largest Corps. (currently anyway) would care to own anymore than two. The "average" sized, current Corp. will want to focus on just one. So how many Corps. is that? It's certainly not 15 so some islands will be "open" even to smaller Corps.
Now let's factor in the advantages of owning a Beta Outpost versus the costs AND the advantages versus the costs for attacking the SAP's of another Corp.
It would take someone with more knowledge of the market and manufacturing than I have to put hard numbers on these variables but a medium-sized Corp. that is currently in an alliance does not get any direct (game-mechanic provided) benefits from being in that alliance if they aren't the outpost owner. The alliance members may choose to trade amongst themselves in favorable terms but station ownership directly benefits only the actual owner.
This won't change in the new structure BUT owning their own outpost, even if it is not maintained at 100% stability, will - or more exactly - can, do so. While outpost ownership will confer cost reductions (even to zero cost) to the owning Corp., it will also require constant "upkeep" costs in the form of ammo and items and bots potentially lost in routinely taking their SAPs.
A Beta outpost-owning Corps. ability to balance these costs against the benefits is tied to how much benefit they can draw from their outpost by manufacturing, mining, refining and selling.
These costs will be multiplied for any Corp. that owns a Beta outpost AND wants to harass another Corp. by consistently contesting the SAP's of that other Corp. I would suggest that, even for the largest Corps., there is no direct benefit in contesting someone elses outpost UNLESS you intend to take it over.
For a Corp. that owns no Beta outpost, there is also ZERO direct reward unless you intend to take the outpost.
I'm not suggesting Corps. won't do this just for grins, but, until or unless there is a game mechanic that rewards a Corp. just for taking someone elses SAP, it's going to be perceived as a waste of NIC and time very quickly.
On the flip side, it benefits EVERYONE if all the Beta outposts are owned by Corps. As stated previously, the disincentives for a Corp. to own more outposts than they can manage to keep the stability high on are great enough to stop anyone from trying to own more than a couple. But, when every Beta outpost is "owned and operating". their value is increased for everyone due to the availability of more goods, more "soft" PvP targets like miners and haulers, more hard PvP targets in the form of "guards" and SAP defenders and by the improved quality of everyone's Bots through a more vibrant market.
Beyond that, alternative types of Corps. and Corp. relationships become viable. For example, a very efficient, skilled manufacturing/mining Corp. may seek to hire other Corps. as protection for their Ops and transporting. Both will benefit. NAP's and alliances will still have value, just for different reasons...and probably on a more transitory basis.
This is all good for the game. Stability is the enemy of a sandbox PvP game...particularly stability that results from domination. Anything that lowers the cost of entry to outpost benefits will improve PO by creating more instability, increasing PvP opportunities and "spreading the wealth" directly through game mechanics.
While, personally, I'd like to see these changes released simultaneously with more of the benefits to station ownership that have been discussed, they are, without any modification at all, beneficial to the game.