Everything here runs under consent — either of you can pause, stop, or change your mind at any point, and "not this one" needs no reason to be honored. If honest feedback is currently hard in your relationship, that's the first thing to work on, not positioning.
Pain is a stop signal, not a dial to tune: don't continue with a "lighter version" unless your partner asks for one. Painful sex is common — 23% of U.S. women reported it at least once in the past year, 7.5% of British women for three months or more — and about half don't tell their partner. If pain repeats in any position, see a provider; the When sex hurts guide covers the triage.
Scope, honestly: the variables above are described for penis-in-vagina positions between a woman and a man, and the body-image and exposure research behind them comes mostly from heterosexual, Western samples. The same variables — support, pace, room for hands, how much exposure a position asks — travel to other bodies and couples; the specific defaults in the table were not written from that experience. And in some cultural or religious contexts, openly asking what a partner wants is itself outside the norm — this advice needs that room to land gently.