Though 'Breakdown' is by no means the worst offender, I'm not keen on maps that are extemely regular and present a 'wall of planets'. I'd also make 6 of the deserts ice/volcanics- the central ones?- otherwise the advantage to civics is very marginal.
Breakdown isn't going to have much emphasis on civics simply by virtue of its highly aggressive layout. That equidistant desert between you and your opponent is going to be a flashpoint at the very start of the game unless it has a lot of militia. I guess I could swap that desert with the ice/volcanic... that change might be worth consideration, but I dislike revisiting maps once I'm happy with a finalized version. That said, if the equidistant desert choke becomes entrenched, the ice/volcanic becomes the alternate approach point and a very valuable asset.
On 'Nightmare' Player 1 seems far from the neutrals, perhaps you should take jump distance into consideration?
Without actually overlapping phase lanes (it would be virtually impossible to decipher the mesh), I can't keep standard phase lane lengths on this map. It's the same deal with Quagmire. I changed the scaling of the map so all phase jumps should be fairly short. The longer jumps may be three or four times longer, but there's not a huge difference between three seconds and twelve seconds.
'Quagmire' another map with a preponderance of deserts, seems to also be a regular map where the outer jump distances aren't compensated for?
I very specifically counted out the planets on Quagmire (how I counted) and I can assure you there are exactly as many ice/volcanics as deserts. Beyond that I made a lot of effort to ensure that the ice/volcanics were typically of higher strategic value to encourage investing in the civics.
Again, due to its layout I cannot do much about phase jump length of Quagmire. It's an inequality that will have to be lived with, but I don't think it should be too noticable.
'Separation of Powers' is the sort of map far more to my liking than 'Breakdown', though four Gas Giants might be too many.. of the neutrals are Gas Giants the most pro-Vasari?
There are three neutral gravity wells per player on these maps. It's on the high side, but still within what is considered acceptable.
With the 2v2 and 3v3 versions the pirates might be improved if they were connected to the pair of ice gas giants on each side, rather than or as well as the sun?
I like this suggestion a lot, and I'm going to go back and make that very change (it will be instead of the sun; I don't want the pirate base to be a shortcut.
I'll also add that there was a mistake on the 1v1 version screenshot I posted that has since been corrected. The gas giant that connects to the volcanic is supposed to connect to the ice, and the other gas giant was supposed to connect to the volcanic (the layout is correct in the 2v2 and 3v3 versions).
The neutrals you've used are variable, perhaps Separation 3 per player, Quagmire 3, Nightmare 2, Breakdown 1?- though on some maps they are easier to get at than others, 1 neutral per player isn't many?
I follow the rule of 2 ±1 per player, so they're all within reason. Breakdown has fewer colonizables per player, so it makes sense that it also has fewer neutrals in total. Quagmire has more planets per player, and therefor it makes sense to have more neutrals.
Might it not be best to whittle the maps down to a much reduced set that players could get used to, rather than expand further, though...?
This is open for discussion. I personally have no problems staying around 50 maps total and cycling in new candidates and removing old ones that don't work out.