1. Arbalest, mortars, piliums, kites, gremlins, hounds, cerberii, wayfarers, mules, buffalos mk2, ventures, atlas & prometheus mk2s... There would still be plenty of mediocre equipment and ships around to feel good about your own fleet & rebuild quicker.
I think the real problem is that it is trivial to
skip all these things. Generally we only ever have to use them in the incredibly-short-term before picking up the item we actually desire - from the Black Market. And that is why they feel useless. They
should be things we have to use, because we
cannot grab something better (yet) - but they never are.
I think it is better to fix that flaw in the design than to just discard them and power creep away.
(It would, of course, almost necessarily result in power creep - when new items would have to be "exactly as good" as existing ones, the design space will soon be spent, and with "worse" not being an option they could only ever be "better". Then the old items of today become the bloat of tomorrow and the cycle repeats. I hate it, when that happens.)
2. "more-than-half the ship for half the ship's cost" - and less op, an stat frigates can't afford to sacrifice
You can fit 2x Light Needler and an Antimatter Blaster and still have enough OP for Hardened Subsystems and Solar Shielding before S-mods. What more do you want? Mine are working fine and I would not want to miss them.
(OP are a bit tight on the Shade (P) but its system is the "main game" anyway, so I can e.g. drop the Antimatter Blaster for Heavy Armour or downgrade the needlers to Dual Autocannons and that also works.)
... Sure, the pristine skins also work fine and do work better, no question there. But they do not work
twice as well, so it does seem clear cut to me to take the (P)s over the "good" ones every time. (I sometimes pick up a few pristine ones in the early game to train officers on, but they always eventually have to go.)
Long story short:
Useless these two hulls are definitely not.