While I wouldn't pretend to be an expert on the military techs of all the other races, as I was the one who suggested a complementary military thread to Darvin's survey of financial techs, and no-one else took the hint, I decided to try to produce one.
Planetary Shields- Overrated even before starbases, as they were most useful against siege frigate raids and before the carrier cruiser revision, when the ships couldn't simply take the shield generator out first. When starbases allowed the retention of planets despite bombardment they became wildly overpriced, as what you then pay for is the difference in credit income between a bombed planet and one that isn't bombed, rather than all the investment in infrastructure. They're even higher on the tech tree than the starbase control of planets... on a volcanic planet or roid the Vasari ability to keep planetary control is so much better than this that it becomes derisory.
While the novalith has also lost some of its value due to starbase control of planets, it isn't nearly as badly affected as planetary shields, at least a novalith will still have some targets, whereas anywhere you would have built a shield will have a starbase as a priority.
Solution: Many solutions have been proposed, but the most basic problem is that this tech is just incredibly far up the tech tree for what it does in the game. I would suggest that with the arrival of the starbase control abilities, tier 1 and tier 2 might be more appropriate for the research, unless the effect of the research is radically altered. Even at tier 1 and 2 and with reduced cost, I doubt there would be many of them.
Martyrdom- The seekers have only just disappeared! We don't want them back! However, as this ability costs a ship, the damage might be very poor. I haven't ever seen it used online, and I've seen a great deal, including sort of crop circles made with turrets and my feed being used to build multiple cap ship factories. Having said that I've rarely played Advent so I'm not sure, but I wanted at least one Advent tech in the four.
Solution: Is this damage straight or mitigated? Either way, improving the damage would seem to be a straightforward solution.
Wave weapons- Another perennial is that improvements to wave weapons are too expensive, as they are too high up the tech tree. The tech just requires vast numbers of heavy cruisers to make it remotely viable, rather than building another cruiser.
Solution: The obvious solution would be to bring them into line with other techs, drop them a tier. However, as more variation should always be encouraged, why not make them twice as effective instead, 10% not 5%? Vasari ships still tend to be undergunned, and at a high price this could then be altered.
Pinpoint Bombardment- I'm not sure what this tech was ever intended to achieve, a 13% increase in the range from which bombardment is possible doesn't sound much for a tier 1 tech. You can buy a whole scout for that. I wouldn't buy it.
Solution: This one just needs to be completely redone. If it's to stay where its is on the tech tree then I would suggest that it should allow destructors to also have a ranged anti-structure attack like ersatz assault cruisers, only not nearly as effective. Either that or add to the starbase anti-structure weapon, though then it would belong in a different tree. Maybe both?
So there we are, I'm sure that there are many other candidates and suggestions, but let's stay with military techs rather than capital ships and their abilities, which belong on another thread.