Anecdotally, as a virginal twentysomething, long before incels were a thing, I had the idea that I might be better off targeting the lower end of the beauty spectrum. I don't think it makes much difference to your chances of success. Women don't generally think "well seeing as I'm physically hideous, I'd better accept this unappealing romantic offer". I eventually ended up having some totally hot partners, as well as rejections from less conventionally beautiful people.
There's also the issue that you probably wouldn't have a very active or joyous sex life, which your partner will probably have a problem with even if you don't.