Few things which may not even really answer your question but could help you:
Way too much sharpening occurred in post. Keep it subtle, especially with something artistic it's better to be a little unsharp than to overdo it.
For cropping, well try not to really. Focus on getting different angles in camera. Get closer, focus on different parts of the plant. Macro lenses or adapters might be helpful too. If you want to get more creative shots than you need to get more creative with your techniques. It takes time though.
Your shots lack a lot in terms of color and depth. The whole yellow cast detracts from the colors without a clear artistic vision as to why. So if you want it to be yellow go all the way, if you don't want it to be yellow then fix it. Depth wise there are some dark areas but rest is all midtones. The over-sharpening doesn't help with some of the edges in this regard as well.
So here's working off your jpeg if I were to want to let all of those colors and depth come out:
As far as positioning vs cropping. The first thing is if you want to do an abstraction to think about what abstraction is. It's really about a part of the whole, just an idea of it. So you're starting from a weakened position that cropping may not be able to help because you photographed almost the whole flower. This might be an idea of an abstraction, granted it's very small because I'm just cropping:
Now I can't tell really what that is. Except that should've been done in camera or much closer anyways. Cropping from a full flower to a piece is going to really lower the quality.
Here's one I did of this flower a while back. Is it great? Meh, probably not. But might give you an idea:
Here's a different flower and one that I never even shared before because I wasn't particularly impressed either way with it and I'm very picky but again might give you ideas:
Notice neither one can you fully tell what's going on. It's a part rather than the whole. If you're looking for abstract photography of flowers and plants than I think that's the main thing you're missing. Abstract is about giving the viewer just enough that they can kinda tell what it is but leaves much to the imagination. Like it could be a flower but it could be something else entirely. It's about the form, color, and lines rather than the object.