Girl on top is great, and I love the reverse cowgirl variation. I also love that position with me sitting on a couch or chair and her squatting over me. I usually finish doggie style, I'm so glad my current partner loves that position!
when you are my age, any position is pretty good! Doggy style is great for me but not for her so we do a modified version where i can stimulate her while i, well, you know what i mean. Otherwise , gal on top.