There's not much to wiring up heated grips. If you choose to do so, buy the grips of your choice (there's a thread on these) and study the directions. Find some Youtube videos of the installation. Go to your regional thread and ask for help. With all the materials in one place, it shouldn't take more than a few hours from start to finish.
I use Hot Grips because I always have and they're simple and reliable, but that's just me. Also, the directions are really simple. It's a fun project.
For certain, you'll be pulling the tank and seat and you'll need some ability to solder or crimp, or the ability to lure someone who can solder or crimp.
I've used StaBil for decades for stabilizing fuel and I've used Seafoam for almost as long to keep things running smoothly, especially with fuel injection systems. Follow the directions and, yes, run it in before shutting down.
If you do add more electrics you may find that you do need to periodically charge the battery.