my grandpa had a nissan 2 stroke that was i think 10hp for decades before he sold his jon boat. but if you are getting something small, just get a really powerful trolling motor. I use a 55lb thrust on my pontoon, and I can haull ass with it; plus you are burning no gas, and they are so much cheaper. you can get a 75lb thrust for the same price as a tiny outboard motor

1 hp equals 65 lb thrust.  A small outboard is just as light if not lighter than an electric and deep cycle battery, while providing much more power.