My work straight tail C-172 didn't have any paint except for the N numbers. No seats except for the front left seat. Flew with the doors off a lot. Restricted Category. IFR with autopilot..
Good idea ... most folks do not stop and consider how much weight several gallons of paint will add to the aircraft .... and that is also one of the reasons it is best to strip the old coatings ... otherwise the paint-weight is doubled.
I am sure you know this already ... the most important next steps are chemically treating the aluminium (Alumiprep etc) ... then a good quality aluminium spec primer ... get that right and the paint will last practically forever .
I always used IMRON Polyurethane but it can be difficult to apply and most painters shy away from it unless experienced ... but there are many very good automotive acrylic urethanes available today that are excellent and easier to spray for the average painter ... like I said ... the prep and primer are most important .
Imron is really a easy paint to paint with compared to some of the others. Good to used on an all aluminum airplane with a good prep and primer.