These look like your average everyday GFX. What I mean by that is that they’re high quality, and that I can see them being thumbnails / advertisements for any game.
I love these! You can tell you have the experience and know what you are doing. At this point of your level, it’s really narrowing it down to creating things that will make you stand out. I would love to see more accessories, maybe less popular assets on characters and etc. Also, color grading the rig picture will make it blend in with the back much more.
Definitely I can see you understand the concept of not having much small details, because these kinds of pictures are meant to be seen from a very small scale. So anything that will make it pop out and have large detail