Lift bag aren't accepted as redundant buoyancy by some agencies (i.e. TecRec). Check with your instructor/agency to determine that.
Drysuit is generally accepted as redundant buoyancy, although this has to be accurately calculated, in line with your overall weighting and buoyancy requirements.
Double Bladder wings aren't accepted as appropriate by some agencies (i.e. GUE and UTD). They favour drysuits and/or '
balanced rig'. Balanced rig is where the entire system is calculated to enable the diver to swim the kit up - normally the approach used when diving wetsuit. Choice of cylinders is critical to this.
There are many approaches to 'tec diving'. Confusing as it may be, you need to isolate which approach you wish to follow and tackle your gear configuration from that perspective.
Given your stated experience, I'd suggest that you would benefit (
and ensure an acceptable measure of safety) by undertaking some specific training on the use and configuration of technical-type scuba equipment. Most technical diving instructors offer some form of intro-to-tec course... 'taster' courses or equipment familiarization courses.
Using 'tec diving' equipment, without appropriate training or procedures, can actually create more dangers than it resolves.
