1) More Strike Weapons, including some sort of ballistic non-bomb Strike Weapon.
4) Some sort of AoE Energy PD weapons, similar to Flak.
5) Some "Fast" Low-Tech and Midline ships that can match Hyperions and Tempests in speed, if not efficiency.
6) More, better armed Low-Tech Frigates that have firepower to rival Hyperions and Tempests. Currently the only Low-Tech ships that field Medium hardpoints are the Brawler and Hound, and the only Midline is the Vigilance. We need low-tech and midline ships that are as known and feared as the Hyperion and Tempest. Some definitively purposed "Strike" and "Assault" ships would be ideal.
7) More "Slow, but powerful" High-Tech ships. Currently they're all about hit and run. They need some that are about staying power and endurance.
More versatility in the tech levels in general. For example, low-tech lacks a "Fast attack" frigate, high-tech lacks any carrier but the Astral, any frighters/tankers whatsoever, and any Destroyer but the Medusa.
I like some of your ideas, but I strongly disagree with this push towards homogenization. I like that there are things ballistic weapons can do that energy weapons can't, and vice versa; I like that the ship designs from different eras follow different design principles. If you want a big ship that's about staying power and endurance, you get a Dominator or an Onslaught. You seem to be treating the different sets of ships as though they're from mutually exclusive factions, which they're not.
IN GENERAL, Tri-Tachyon ships are the best right now and not much can match them. Adding some more useful Low-Tech and Midline ships is probably needed.
The high-tech ships aren't the sole property of the Tri-Tachyon Corporation; TT just prefers to use them and has the resources to build and maintain them (the fluff text for the Astral, for instance, says that they serve in the Hegemony fleet, albeit in limited numbers). The way the placeholder campaign is set up, yeah, Tri-Tachyon gets all the techy blue stuff and the Hegemony mostly the hulking low-tech gear, but I'm sure there will be more variation in the eventual 1.0 release (plus, you know, more ships in general, and more factions, including the Cult of Lud).
The high-tech ships are the most recent designs, and they are, explicitly, the most technologically advanced. That doesn't make them the best in all circumstances, though, and it
does make them (or will make them in the final game) the rarest, most expensive, and hardest to come by. In fact, right now the Hyperion and Tempest cost as much as the midline cruisers.
Also, take a look at the first three points on your list, following "Tri-Tachyon ships are the best"—criticisms of three of the five high-tech fighter wings, all of which Tri-Tachyon use. You then call for two of the midline fighters to be nerfed. So, you know, the high-tech/low-tech disparity isn't so bad across the board.