The 20s do look a little on the big side, plus those are only 215/35 20 tires. I couldn't see riding on those rubberbands.
I had a bagged 90 C1500 on 22s and loved it. Once you found the sweet spot, the ride was great. Plus, I loved pulling up to donks and laying it out on them. Really pissed them off.
If I ever get the money for the front struts, I will do airride on mine. I already have some bags for the back, air tank and valves. Compressor and universal air struts from air lift are all I need as far as major expenses.