Air bag suspension help

So I'm building a air bag suspension for a project truck my friends and I have been...creating (not my taco).
I've got a couple compressors, and 7gal tank which might get swapped for a old scuba tank (don't ask), manifold (with controller) and a bunch of rando odd crap connectors. Bags are already on the truck.
Looking for some input regarding 3/8 vs 1/2 air line. Pretty set on using push to connect connectors.
Have a muffled exhaust valve thing with adjustable release as well to control the lowering phase. Truck will mainly get aired down for fun/creat a spectical/hide all of the leaking fluids.

So my questions are:
1/2 vs 3/8 air line?
Good place to buy fittings and hose?

Also feel free to throw in any other general advice or words of positivity and support I expect from tw....

 

The bigger the line, the faster the rise/drop. I went from 1/4" to 1/2" and it made a pretty big difference.

 

I agree... but with those muffled exhaust plugs (I believe he's referring to the cork looking ones) it may slow down the drop will be affected and not drop as fast