re: "crimp them due to them being 20 or 22 AWG wires."

Crimps for 20 and 22 AWG wires are readily available, but not in many marine supply stores. It's pretty much an electronics wholesale item (or maybe Radio Shack...seems they have less and less "useful stuff" these days"). What I don't think you will find, although I've not done an exhaustive search, is the splicers with the built-in heat shrink sleeves at 22AWG.

After many years of using a soldering iron on a very regular basis in my work, I usually solder everything and don't use crimp splicers, ever. I cover all soldered splices with heat shrink tubing and have never had one fail even after many years in a marine environment.

I've found that the biggest problem folks have with soldering electonics is trying to use a cheap and/or underpowered iron for the job at hand and the wrong solder/flux.