Well, I think I played enough of SE IV to say that stealth armor is a very much unbalanced feature in the game.
Consider this: for every offence there is a defense, and the defense is usually less costly. That is the way it should be - the attacker has the huge advantage of surprise, and concentration of force.
Examples: PDC are cheap, missiles and fighters are expensive, the self-destruct device is much cheaper than boarding parties (and security stations are more effective), shield depleting weapons are costlier to research than shields themselves. Ships cost more maintenance than bases. And so on.
It is the same way with cloaking vs. scanning: cloaks are expensive to build and hard to research; scanners are cheaper in both respects.
BUT: Stealth Armor is extremely cheap (and you gat it along with the regular Armor and other benefits), and once you get it you can do stealth attacks, which gives you a huge advantage. Counter-measures? They are rather expensive...
As a result, Stealth Armor is a MUST, and there is no way around it. Once everyone gets it, they put it on all ships, and then before scanners are researched the game becomes more of a guesswork than a strategy game. This is what I call an "unbalanced feature", when you do't have a choice about it.
Of course this all does not matter that much in HUGE galaxy games or games with all-tech start. But if you are playing a 4-player game in a medium galaxy...
Does Stealth Armor need to be changed? E.g. if it's Armor VII - Armor IX instead of Armor IV - Armor VI, it would become much more palatable
Aub