Personally I dont see any point to upgrading the weapons until your defense is upgraded. I also dont thinks its worth it unless you can get the full benefit that means upgrading everything for a weapon range. Which for the price doesnt seem worth it when i could be making more ships and upgrading defense.

Just to list whats unbalanced
TEC Repair frigates and Command cruisers abilities and weapons range make them exploitable
Illuminators Enough said they are the best unit in the entire game.
Colbalt whats the point?
Returning armada- This wouldn't be a problem is the tec and Advent equivalent to this existed but it doesn't the best you can do with tec is power of industry and insurgency. I don't Think advent even has a second super weapon there entire research revolves around fighters, defense, and culture.

unless you plan to play a match several hours weapon upgrades are not that important, since there realy expesive, take time and dont give lots of reward any time soon.

1) Advent's Malice needs to be buffed because it was excessively nerfed. The number of targets it applies to should be increased. Currently I think it's 8, 16, 24. It should be 8, 24, 48. Otherwise, the damage should be applied instantaneously again.

2) Returning armada should be restricted so that one instance of it can run per planet, not per structure.

3) TEC's Marza needs its planet bombing ability buffed significantly to make it worthwhile. It also needs the ability's radius of fire to equal that of the radius of fire for the regular bombing weapon so that the Marza doesn't start bombing the planet while simultaneously sitting just out of range of bombing ability thus preventing its automatic use.

What you say might be true if you were only going to play a small map in a game that would be decided in under 30 minutes.

The real determiner of whether or not it makes sense to upgrade your shields, hull, armor, and weapons is the size of your fleet and whether adding another ship or two would strengthen your fleet more than making an upgrade. Also, when you've maxxed out your current fleet supply and don't want to pay a higher fleet tax it might make sense to work on military upgrades (unless you've only maxxed out the starting fleet supply or the first fleet supply limit).

Shields, hull, and select weapons upgrades should be a core part of your strategy. I get the sense after reading your statement that you just play the game against dumb AI in forgiving single player mode and not the real game (online multiplayer against humans).

Main problem I've seen so far is that the game places too much of a premium on early aggression, and too much advantage in the hands of the attacker. Few defenses worthy of the name are available early in the game, and this is entirely unrealistic in terms of tactics (yeah, I know, "real world in Outer Space?"). It's what gives the Zerg-rushers (pardon, 'spammers') the ability to operate at all.

A real-world defender typically has a major advantage over an attacker, in any reasonable tactical simulation. Normally it's figured at about three to one - - in order to guarantee success, an atacking force should have a 3:1 advantage over the defenders, to counter the natural advantages of defense: short supply lines, no need for mobility, rapid replenishment, and a fixed firing base that can be of immense size compared to anything mobile.

What's needed to balance the game and turn it into something other than a footrace & spamfest, is a premium gained upon defense, and some reasonably strong defenses being available early in the game.

Attacking ships should be easy, but defeating an entire planet should be a much more major undertaking... and the planet's ability to aggressively defend itself shouldn't be 100% dependent upon orbital resources, either. It's a PLANET.

Most games are decided in the first 30 minutes, should do something to make longer games more viable. Also, make it so that you can have team start positions. (these are balance changes, but not race balance changes)

I'd also like to see technology play a larger role in who wins battles. In this game, the larger force wins, no matter what. 10% more firepower on one side or the other is too minor a difference to be significant. Like was said above, the upgrades only make sense when you already have a huge fleet. The extension of that thought is that upgrades only make sense in long long games.

Personally, I like to play games that are significantly under 2 hours, so I basically never upgrade unless my game goes longer than average.

I'd like to see small fleets destroy bigger fleets.