Something I think is good? somewhere south of 5%. Something I think is Great? Maybe 10 shots in 35 years.

What does the contract say and/or how bad do you need the money?

Art is subjective so its hard to tell what someone else will like. You do seem to have more than a few slightly underexposed and out of focus pictures though. I wonder if you are just shooting everything wide open? Also maybe pick the best couple from a set? No sense posting 20 pics of the same bug or squirrel. Are you trying to make a living with the subject matter on your site? Not sure theres a huge market for this kind of stuff. Why not try selling at a stock photo site. Real quick and dirty way of finding out if your stuff is marketable.

Nope. Not in my opinion. Nothing beats lightroom as a whole package. There are alternatives that do some things better but as a whole I don’t think they can really compete.