[Q]

I have done something like that in my modifications:

1.) I doubled the cargo space of planets and make domed planet hold half of the cargo of non-domed planet: So domed colonies have the same cargo space as non-domed colonies in standard SE IV.

2.) I made weapon mounts for weapon platforms with up to an increase of the range by 6 and an important increase of the damage done.

3.) Created shields for weapon platforms that are 50% stronger than for ships.

4.) Increased the damaged needed to kill population by 3x.

The AI handles this quite well, it even helps him because in standard SE IV frequently his production is blocked by "no storage capacity available".
And it's really hard to knock out a decently developed colony in this modification!