Many/most of the blind rivets I drill out end up spinning in the hole meaning I can't finish drilling them out. In other words, the rivet starts spinning as fast as the drill is turning. Another nice thing about aluminum rivets is that I can take a half inch (sacrificial) chisel, lay it flat against the surface, bevel up, and lightly cut the head of the rivet off.
once told me that the drill should be no more than 1/64 inch over the diameter of the rivet.
In a sort of "belt and suspenders" approach I'd suggest a very small dab of silicone in the hole before inserting the rivet and more over the hole after the mandrel snaps.
Pneumatic riveters can be expensive unless you buy from Harbor Freight or some such place. They would probably be adequate for the relatively few rivets (compared to a production tool) you need to replace. Some rivets can be awkward to access and a pneumatic might be helpful. However, hand held riveters are more than adequate.
There must be some sort of guideline as to length of rivet but I don't know it off the top of my head. Often the rivet is holding something to the outer skin. The body of the rivet has to be perhaps an 1/8" longer than the depth of the hole. (Not counting the little bulbous end to the mandrel.) I'm making this rule up as I speak, hoping someone has a more authoritative guideline.
Intuitively, it's a good idea to press the layers to be riveted together before pulling the rivet. It can be a two person job, one inside pushing things against the wall, the other outside running the riveter. In my case, being single, I use creative bracing to hold things in place.
Backup washers are very helpful as Brian suggests. Use them wherever the inside of the rivet is hidden. Casita
puts an acorn nut over the ends of exposed rivets to dress up the appearance. I'm attaching a drawing I've posted a number of times.
You need to experiment with a nut size that just fits over the unexpanded rivet diameter. This might not pertain to your application however.