and I'm not interested in a wing setup because it doesn't seem comfortable and it is meant for tech divers. .
who ever told you that lied to you. It is meant to be the optimal solution to backmounting tanks. It is what the sport started with at day 1 and continues to be the optimal way for most people to dive backmount. I have logged hundreds of hours in a Halcyon Eclipse system in nothing but a bathing suit. It is not the most comfortable system to walk around in, but that is easily remedied with slide on neoprene shoulder pads or simply wearing a t-shirt.
Air2's are not the best way to share air and if you have ever had to do it in the real world, you would see why.
In terms of gear. $3k is a lot of money.
$500-DSS BP/W- Arguably the best backplate and wing system on the market
$850-Shearwater Perdix-definitely the best computer on the market
$860-Apeks XTX50/DS4 package. Would prefer it to be with DST, but beggar can't be choosers
DS4/XTX50 Single Tank Package - Dive Right in Scuba
Total is about $2200 and everything is better gear except the regulators which are a splitting hairs and some will say one is better over the other. The BC is much better, the computer is infinitely better, and while I don't personally like either of the regs, it really doesn't change the fact that they are the two most popular brands out there and are high quality regs. Apeks has free parts for life, which is stupid because it forces you to pay an insane amount of money for maintenance the gear doesn't really need, but such is life, if you want it, you want it.
My personal gear?
Backmount BCD's are Deep Sea Supply
Sidemount BCD's are Hollis, Dive Rite, Razor
Fins are Dive Rite, Scubapro, HOG, and soon to be Deep6
Regulators are Poseidon except for O2 which is a 30+ yr old Dacor Pacer
Masks are Atomic and HOG
Drysuit is Rofos
Wetsuit is Oceanic
Hooded vest is Scubapro
Computer is Shearwater
Lights are UWLD, Securitying, Cave Adventurers, and Big Blue
Not a whole lot of overlap, and that's good. IMHO DSS makes the best backplates and wings on the market, Hollis currently has the best sidemount rig, Deep6 has the best fins, Poseidon has the best regs, Shearwater has the best computer, and UWLD has the best canister light. The rest of the stuff is personal preference, stuff that I got for cheap through knowing a guy, or bought used for cheap. Hollis makes backplates and wings, computers, regulators, and fins. None of them come anywhere close to the other brands that I use in terms of cost/performance/quality. They're all good enough and I would have no problem if Nick decided to give me a bunch of free gear and ask me to dive it, but if I have to pay for it, I am going to buy what I believe is the best. No one brand is able to do that, and really nor should they. Let them specialize in their own particular niche because they will be much better for it