I am by no means an expert in the homebuilt world. My experience is helping to build a Thorpe T-18 in the 70's and helping rebuild a wrecked Super Cub.
You can get engines certificated for car gas. Since this is my first plane I will be following the directions to a "T".
Like you, if I win the lottery and can get a fleet of planes to experiment on, I may start thinking outside the box. :-)