Seriously, look into a balanced rig. Most tech diving classes do not teach ditchable weight.
Maybe I'm misreading your posts, but it sounds like you are having a problem swimming up your steel doubles in a compressed wetsuit with a wing failure. If you are setting up your rig so that you will be neutrally buoyant with near empty tanks in shallow water, then the only thing that is changing (i.e. that you would have to swim up in a wing failure situation) would be the weight of the gas plus the lost buoyancy of your wetsuit. Ideally, this is the amount of buoyancy that you would lose with a wing failure, because the only thing that your BC is used for during a dive is to compensate for those two things - it should be empty at your last stop (assuming that you used most of your gas). If it isn't, then you are overweighted..
This is one of the reasons why people don't dive heavy wetsuits with steel doubles, the buoyancy swing can be pretty large. So if your steel tanks don't let you swim them up, you could use aluminum tanks and add just as much weight as you need to make your rig neutral. And you don't have to wear the weight, you could put it in a V-weight pouch between your tanks. Much closer to your center of mass that way, it doesn't shift around like a weight belt, and can't be lost inadvertently with a deco obligation.
I know that it's a pain to get rid of stuff that you already bought, but tech diving is a big financial commitment. You shouldn't cheap out on your gear, it really has to be dialed in. Steel doubles hold their resale value, since lots of tech divers dive dry, where the extra weight is welcomed. You should be able to swap them for double AL80s with money left over.
You can't get a "cave fill" with AL80s the way you can with LP85s, so the steel tanks would give you a bit more gas. On the other hand, not every shop will do that. Also, you could get double AL100s (although they are a bit more negative).
