Your first two photos work for me, especially the 1st photo. The blue against the pastel beige/brown works well not to mention the interesting subject too.
My 24/1.8 is sharp as a tack, while my 35/1.8 is less so, mostly noticeable at closest focusing distance. But I don't really concern myself because these focal lengths meet my needs and are better than my film lenses of old.
If you use Mac computer or iPhone, Apple's 'Photos' editing program is excellent and intuitive to use.
It's my main editing program because it's so easy.
If you were pleased with the 28-300 on your D750, it will be better on your D500 equivalent to a 42-450mm, and not having to contend with soft edges. Should get you in the door to wildlife photography. Looking forward to seeing your photos Sam.