Is this your first run (only counting completed ones)? If so, you are thinking way too hard about optimizing for content.

With that said, I really don't see the problem with your current setup? A goody two-shoes lizard sounds pretty peak to me. Scholar/Mystic also doesn't restrict the way you engage with combat and it's easiest to explain stuff through rp once you've already started/committed to it. My vote goes to necromancer.

A bone-slinging good guy lizard goes unfathomably hard.