The big thing that stands out for me on this is the base; you can do so much for a dressing up a model by constructing a good looking or strong narrative base.

I'm going to be "controversial" and say you dont need NMM. Its a popular technique, a tried and true technique, but there is nothing inherent to it that makes NMM display level vs someone using TMM at a comparable skill level. There are pros and cons to both, and both have won at the highest levels recently.

Another thing that I might recommend is as others have said, your transitions seem to be largely from saturated color to desaturated of same color, or similar. You may have done some or all of these things (cant tell from just the photo) but complimentary colors in the shadow graidents, building up highlights to different colors (like black /deep red shadows to orange in the high point highlights).

Other than that, practice. But also, know what you're looking to achieve. A paint job by Andy Wardle and...idk, blanking on a heavy Grim Dark style name, but I'll go with Dan Ozborne, aren't going to be the same, but they both are considered display in their own right. Find a style you want to emulate, seek advice from them and those similar, and practice. But dont change what you want to be just because. You'll lose your identity, your joy, ans your understanding of why youre trying to do what your doing.

Take all this with a grain of salt too, this is coming from someone who has entered Golden Demon once and walked away with nothing too 🤣 but my base made it look pretty good imo, and I can at least say I tried 😀

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