Hi
The reason the paint job you did failed is because rattlecan paint like rustoleum needs at least 6 months to gas out and cure. I wouldn't paint the bike with rattle can again but if your budget is low just do it, probably after a month or a week the paint will start cracking or getting pretty bad as in your 1st picture. I would not surprise me either that for every part you put in the bike the paint simply peels off or crack. It the nature of that paint.
Asnwering your questions.
1 - No, if you want something durable i would stay away of that paint. 2K urethane paint or powder coating is the only thing that will last.
2 - Well if you insist using rattle can not even putting 4 coats of clear coat will help because the rattlecan clear turns yellow because doesnt have UV, simply bad paint.
3 - U want to color the rims? I would not do it with rattlecan. Painted rims are powder coated and some are anodized, car paint could work too with at least 3 coats of polyurethane clear coat over them. If you want to paint that u have to sand it to etch the rim surface but prior to that I would unlace the rims to paint them right or it will look like u know what!.
If you want to go with car paint the expensive part is the clear coat, only a small can of clear can cost 60 bucks but the quality is like 1000% better than rattle can. If you budget is like 40 bucks continue using rattle cans.
Good luck