Ride quality, coilovers vs bags vs lowering springs?

[a1960apache]

Hello all can anyone comment on the ride quality and handling on lowering springs with stock A arms, new tubular trailing arms etc, coilovers (ride tech, pbfab etc) and air bags, and lastly a PBFab coilover setup front and rear? I don't plan or need to go too low, maybe drop 4-6" so I am trying to figure out which way to go. On the low end I could just use lowering springs or air bags on the stock suspension, or move up to tubular A arms and trailing arms with sway bars front and rear, or go all out with a PBFab front and rear coilover setup. Also which setups center the wheel in the wheelwell opening? Getting that looking good is worth a fair amount of extra money and I don't know why they didn't get it right from the factory, not to get off on a tangent but most manufacturers still don't get that right, the trucks look great but every time I see a new Corvette I can't get past it and it ruins the look!

Anyway, just looking for input on return vs investment, I hate that big old front crossmember but it's paid for, I would rather put the money into big brakes and wheels. This pic is about the exact drop I am looking for.

Also as long as I am here, any good guesses what size wheels those are? I compared the pics to others and comparing the brake rotors, they seem to be 20's front and rear.

Thanks!