I find that when I hang onto uke very firmly, I am often setting myself up for a reversal. You might ask a training partner to explore the possibilities with you. In particular, can uke use the same arm lever you're using and throw you backwards?
One of our junior instructors was demonstrating, as a "don't do it this way" exercise, a form of this throw where nage clamps uke's arm into his armpit. It felt pretty strong if uke was doing the expected things, but it turned out that uke could center herself and almost effortlessly throw nage backwards with that arm. I was delighted--it was the first time I was ever able to do a throw I hadn't been taught, just by feeling that someone was out of balance.
Give it a try. Maybe you'll find that it's a sound technique, maybe you'll find that it's crying out for a reversal, but in either case you'll learn something.