To some extent I agree. Bigger maps means more territory to have to control and makes it harder as well as easier for teams to retreat, regroup and recover during a war. It's why Earth is so competitive. You lost a battle? Fall back and recover. On mars and fantasy, there's no such thing really as the maps are smaller. But at the same time, that's interesting in itself at times. The problem mostly comes when the competition is low and the map is simply steamrolled. But I don't think mars was EVER big enough of a map to stop steamrolls from happening.
We could likely bring an event with this kind of thing, but I don't think overall we'd see much of a change in gameplay unfortunately.
As for the corner gates... I have to say no. Least not the same as they were before. It allowed for some... complications.. (like hiding your army in the gates so no one could kill it). It would definitely change up some tactics and strategy on the map no doubt, but at same time, I found some fundamental flaws in the set up to begin with. It made Russia, Alaska, and Antartica vulnerable, but still allowed Australia and New zealand to be defensive fortresses. And at this point in time, I'm not sure it's worth the effort to attempt to recode that aspect into the game with alterations. That was an OC feature, meaning it no longer exists in NC coding. It would have to be coded into the game as a new feature and that, simply put, isn't free.
Cost vs value here. Nice little feature that COULD be changed and implemented better, but will it return it's cost? Honestly, not sure.