Hey. I actually like your use of color here but I am a sucker for a bit of muted colors, so I might be a bit biased, haha. I like your painting and was also drawn to specifically the wasp and the wings - they where really nicely handled! You made the wings very subtle yet destinguishable. I am not great at color myself since I've also avoided it for quite some time - so take my advice with a grain of salt; but I can also, as Smithies said sense that there are some values in the flowers that may not work with the rest as well as it could. It might be that your lights in the flowers are a bit too light (just a smidge) - especially the parts of light that are hitting the stems. I think it may make some of them look a bit unnatural Also, I know your reference-picture has quite the more vibrant colors and the lights on the stems are quite intense, but the darks and midtones there dont go as dark as in your image - so since you have made your whole image a bit darker and subdued in terms of value - the brights on the stems really stick out. I've attached an image highlighting the shadowshapes I'm seeing on the reference along with a comparison of the values on the reference (top swatches) and your image (bottom swatches). Maybe you can pull something from there? Seeing your adjustments - I still feel there are some troubles with the values in general around the flowers. It's as if you added a viginette to the lower part but I am not sure it helped unfortunatelly (sorry!). I'm rambling a bit.. So I tried to treat it as an exercise myself and I did a paintover to show you roughly what I'm thinking - It might look a bit muddied though. I tried to push the lights down on the stems which kind of makes them look a bit flatter in return - but since your background is very dark I think it's a bit inevitable to end up there without changing too many things. Ah yes, I added just a smidge of light to the wings aswell since I felt the tips could be a bit more accentuated (not sure if it was reallly needed though?). Again, not entirely sure if my changes were an improvement so hopefully someone with more experience can shime in and help you further :P

So, I'm no expert but here are some tips that I think helped me. Similarly to when you put down two dots and draw straight lines - I will sometimes practice putting down three or four dots and doing curved C or S-lines between these dots, while trying to keep the curve symmetrical, if that makes sense? Then I draw ontop of the initial stroke several times, trying to make it match as best as possible. Maybe that it actually what you were doing aswell but it might not have been clear. Anyways, about your hand being in the way; when I practice these I try to find a good angle of approach (generally I arch from the left and slightly up to the right since I am right-handed - but mixing it up sometimes is good aswell). The angle of approach might help a little but I ultimately I don't think you can avoid the hand being in the way when drawing from certain angles :P Another thing would be "ghosting" your lines (hovering the pencil above but not touching it down while doing the drawing-motion). It may be a good idea to help you with your lines' trajectory. I think I picked this up through the Drawabox-lessons if you are familiar with those? I think what I generally do though when drawing without any aid (as in putting down dots) is I sort of imagine a point on the page instead - or an trajectory if you will, and try to make my lines follow through to the best of my ability. It may sound a bit jumbled, but I hope some of this helps.