I teach at a comprehensive state u (not an R1), and while we require research, teaching definitely comes first for us.

My sense is that science folks really need to do something extra to prepare for teaching because there are so many grad student ways to earn basic money that don't involve teaching. (I'm in English; grad students pretty much support themselves in most programs teaching lots of comp and discussion sections for intro classes.) So if you value teaching and can find ways to enhance yours, you'll be very attractive to places like mine.

On the other hand, I went to a state R1, and I had really excellent teachers for the most part (with perhaps two or three exceptions?), and I was a bio major.

Good luck. Teaching is rewarding and challenging in totally different ways than research; and if you're going to do it, it's very worthwhile to do it well and trying to enjoy it. (Now if only I could find a way to avoid grading!)