Girlfriend’s Butt is Too Big

First off, let me preface this post with the fact that I love my girlfriend and her giant ass cheeks. We have amazing sex and are both “givers” so it’s just mind blowing. The mantra, “I’ll try anything once” comes up in the bedroom frequently. The only “issue” is that I rely heavily on visual stimulation to get off. I am of slightly above average endowment and my tool gets LOST when I’m behind her. My past partner’s butts have ranged from small-large, but I could always see my member going in and out of either hole which was very satisfying and stimulating for me. I’ve thought about asking her to spread her ass, but I’ve had females tell me in the past that penetration doesn’t feel as nice when they do this (likely bc of reduced friction). I’ve been having to rely heavily on feel and thoughts to get me off recently which is a change, but could be overall positive. Man, I just miss looking down on that chocolate starfish…any advice?