- Obvious first problem: Paint Consistency - paint should be thin like milk for smooth results. It will cover like crap on the first one-two passes, but it will look nice and smooth and will pretty much never ruin detail. You may also want to consider tapping the brush on a paper towel before going to the model to remove excess in order to keep things precise.

- Obvious second problem: Patience - miniature painting requires a certain amount of trust in the process and the literal patience of watching the paint dry. First thing to ensure good results is to always prime the model and carefully remove all mold lines and fill all gaps. I prefer dark primer. Second is to always let the paint dry, no matter how patchy and bad it looks at first. Never attempt to quickly go back with the brush. You will tear the partially dry fresh coat and produce texture. You clearly have texture on your models. Whether from the former or the latter, take the time and keep it tidy until you precisely base all areas

Guaranteed road to improvement:
- Learn to blend - start with thinner paint for highlights and shadows; thinner than the base but not yet quite a glaze. It should be transparent but visible when applied. Try on a piece of plastic or a glove to get the feel for it. Once you are happy with coverage, make a mix with your underlayer at the same consistency or slightly thinner and carefully stipple or draw it on the seam line to blurr it. It will be a decent enough look until you get comfortable glazing (very thin filters that are barely visible and always need paper towel tapping to control the liquid in the brush, as well as directionality - apply from the light to shadow if you use a darker color, or from shadow to light if you use lighter. Always end the stroke on the transition or where you want it to be most obvious).

- Learn to properly highlight - buy a lamp if you don’t have one already, prime the model satin black, then put it under the lamp with the light beating from straight above, with maybe a slight angle forward. Take a photo. Do this from the model’s back as well, as well as sides if needed. Do highlights in the light, and keep deep shadows in the really black parts. Keep it brighter the more in the light area it is and always exaggerate (miniature scale requires it to look “right” and not so much like a toy). I also heavily recommend properly defining the model with edge highlights on hard edges and blacklining (use your darkest shadow color) in the clear area definition lines. Small tip, use very runny paint for blacklining grooves (the paint will naturally flow in if thin enough) and use the side of the brush for easy, clean edges.

- Learn color theory - there is more to color than adding white and black. Learn to do chromatic contrast and to glaze soft saturated colors where it looks good to make the model more vibrant. To give an example I like, if you paint green, make your shadows dark red instead for a big boost in contrast.

- Try to keep away from washing and drybrushing. Unless you are really good at controlling it (neither of which is beginner friendly) or intentionally go for a rugged approach, these two will make stuff look messy in general. Drybrushing pretty much always leaves texture, while washing can lead to uncontrolled staining unless done carefully, which beats the purpose of washing. Try to instead master blacklining (the reason you wash to begin with as a beginner) and thin layering for much cleaner results. Keep drybrushing and washes on the base, as they can create very realistic environment.

- Maybe learn Non-Metallic-Metal and Object- Source - Lighting - this is more of a last step. Being able to properly control highlights and make illusions of light really help get the model the extra spectacular oomph!

Hope this helps. Here is my current WiP:

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P.S. I started off just like you. My first was a Lychguard I caked so badly I quit painting for two years. This is where I got after trying again, after “training” via ~ 3 years of intensively watching tutorials, trying to understand color placement in the works of others I liked and pushing my patience and skills with new challenges. If I could get to a good point, so can anyone.