[Mylon]

Okay, then how about adding in extra levels in engineering, such as

Level 1 Engineering bay component I (as is)
Level 2 Base Maintenance Reduction I (5% reduction, bases only)
Level 3 Engineering Bay component II (2 repair rate, for people that reduce their repair aptitude)
Level 4 Base Maintenance Reduction II (10% reduction)

If you want, maybe you can add in extra levels of engineering that produce cheaper Versions of life support/bridge or itself, or a third Engineering Bay that doubles as one life support in itself. Or an engineering bay that doubles as a power plant (generates x supplies per turn). Or dare I suggest 15-20% maintenance reduction? Technically a crystaline race with 20% maintenance reduction could have free starbases in vanilla SEIV, but that 20% sure costs a lot!

I'm not sure if it's in the devnull mod or not, but I would also suggest removing the quantum reactor. I actually liked the idea of supplies and catching a fleet out of fuel. But if you do remove them, power plants would be an interesting replacement.

I'm not too fond of the idea of moving bases, but if people want it I don't see too much harm in allowing them one point of movement per turn. If they would be limited by not being able to go through warp points then all the better. Oh dear, the huge fleet of 50 battlestations is on their way! We only have 5 years to build our defenses!

And does anyone have any comments on fighters? They seem to work well early in the game, but when they start getting smacked by combat sensored battleships, they seem fairly useless except as defense for the poor planets that don't have space yards or room to amass tons of weapon platforms.