not sure.  you could always inspect the txt files that control those values.  however, i dont remember seeing any change logs regarding the starbases.

No, starbase weapon ranges are the same as they've always been.  Now, I frequently use an  Akkan with targeting uplink to boost my starbase's range, which is quite effective, but other than that you still have to place them intelligently to get much use out of them.

I'm pretty sure all starbases come with an upgrade that gives them a weapon system with improved range over their other weapons systems.

For example, the TEC starbase second weapon upgrade gives it a missile attack which has longer range than the other weapons; I'm unsure about the range of the beam weapons versus the normal weapons.  The second Vasari upgrade adds a phase missile weapon to the base; this is probably longer range than the others. 

Interestingly, the third Vasari upgrade increases the number of targets they can attack at any time, whereas the TEC need a tier 7-8 research to do so.  This tells me that, through research or upgrades, the starbases probably even out in terms of weapon range and damge per unit of cost.

Stuff like this makes me feel less wary of the overall lack of range on starbase weapons. This suggests that if you chose your upgrades carefully, a starbase that you thought you positioned really well but is getting flown around can come back and draw the attention it's suppposed to. If you have a ton of strike craft coming out of an advent starbase, especially bombers taking a chunk out of their bigger ships, the opponent might be forced to try and deal with the base directly, putting them in range of their other weapons.

Seems like fair tactical balancing. Plus, a smartly upgraded starbase in a small, strategically important gravity well, like with mineable asteroids, would be tough to mess with.

True. I know they still want you to use at least some ships to back up your D, which I think is very cool.

Heh heh. Soft choke.

I suppose if you could manage to get up the cash you could stick two fairly upgraded starbases in say your home system and really bring th pain.

Just to come back to this real quick, a properly upgraded starbase intelligently placed in the gravity well has excellent coverage. At least that's my experience with the Advent. Problem solved itself.