When picking a template, for some reason it always chooses the one on the right for any pair of templates... is there a way to pick the one on the left?

The images on the left are of the Homepage, which is different to the comic pages (the right hand column). If you want to use the blog and homepage, you need to enable it- which is the 3rd tab ("Homepage") in your comic account.

Just a warning though, most people hate the homepage. It can mean extra clicking around to read the comic and leave comments and a lot of people just won't bother if they see the homepage is activated. There's really no reason to use the homepage unless A: you have an adult comic and want to put up a 'warning' page (or similar intervention page, like 'start at the beginning') or.... well there is no other good reason. The authors comments are just as good as the 'blog' feature and don't function too differently.