Any faction can still dom, or invade hexes. But lets say that someone does a diplomacy thread with another faction instead of invading one another. That why they get half a hex. I don't see why not. However, As for the rule of only winning half of a hex in an invasion? No. I am completely against that. Invasions are all about throwing everything you have at the enemy to get the hex you want. Giving them half as a "you tried prize" is bullcrap and doesn't make invasions worth much if every one of them could be half hexes.
Diplomacy threads? sure. Two factions performing dominions on the Same hex, and both are willing to take half? Sure. Go for it. Invasions? No. You either get the full hex, or nothing.
I preferred less hexes....I'll give an example of a reason why:
OPA are cool guys, we've no reason to retaliate against them as far as the SP is concerned....but if they wanted Karra, which is the hex were in....that means Eclipstica (SP CAPTIAL) is now under OPA control...it wouldn't be a bad thing persay...but it's not in our best interest. It's a big fault with the hex system.
I've always loved ways to help better represent the political complexities of Major faction's on Chaos, and I'm more than happy to support this. While the possibilities are there for us to have these storylines already, it's another useful tool in our arsenal to help narratively describe the situation. More border conflicts and invasions to take over "half-hexes?"