1997 Chevrolet Lumina lack of power

Hey my names Steve, and I've been having alot of power issues with my car. Basically when I apply pressure on my gas pedal, my car has a hard time accelerating. When I'm trying to pick up speed, like to get on a busy road or the highway, my car will lag out and I have to let off the gas and reapply pressure until eventually it will kick in, and pick up speed as if I was pressing the pedal to the floor. I've been considering if this might be my catalytic converter, because with my last fix that's what I had assumed and then my engine locked up, because my a/c compressor broke and welded itself together. So after the towing, new compressor, parts, labor, and $400 later I was hoping that was the issue and it was fixed, just to get out of the shop and still have the lack of power. By the way, I don't know if this has anything to do with it, but the lights for my ac, vents, and once and a while my dash lights, dim in and out randomly whether in idle or driving. Its done that for about 2 years now (that I know of). Within the last 6 months I've had alot of issues fixed on the car (cylinder misfires, new spark plugs/wiring, new a/c compressor, new water pump, new power steering pump, new ball joints on both front tires, and a trans flush amongst others) in an attempt to fix this issue, and I'm still experiencing it. Like most I'm not made of money, and its killing my wallet to tend to all these issues, and I understand its an older car and these things were going to need attention eventually, but I would like a professionals opinion so I can solve this issue without rebuilding my whole car and still not having a solution to the original issue! I really appreciate the opportunity to have my question answered, and hope to hear back soon!