I think I know that struggle fairly well, but if you just continue drawing, a lot just ... fixes itself?
Like, if I look at the horrendeous drawings of my characters on the first pages of my first attempt of HttC I just ... I can't believe I actually drew that. By now, even if I didn't actively draw the comic for 2 years, I drew my characters over and over and over and now they don't look off-model anymore because I got a feeling for them, and I think my general facial anatomy improved too without actively wanting to improve anything/working on it knowingly.
Then, of course, it helps massively to work on what you're not good at. I personally am terrible with anything architecture-related that doesn't look like it's going to crumble if you just stare long enough. I still am really not good at anything symmetrical with smooth lines, but I somewhat learned to work around it to just adjust a bit more to that topic - I'm much better at rough sketching, so I made some sketch studies of buildings/elements that I liked, just to work out shortcuts for myself. That way I got more confident and people complimented me on my details even though they were so rough and not detailed at all, but the cool thing is, you can just make it your style. At some point you might feel more confident in what you do and try to work it out more, so you get actually better at it... I think the first step is always the hardest, so uhh yeah, try to find a way around it that suits you without neglecting the issue alltogether!
Also in general trying techniques you haven't used before might help, and general experimenting. This can be a simple "I'm using a rougher/bolder/slimmer... pen for lineart" to "I'm not using any lineart at all" or "let's just throw all colours away and make everything monochrome" etc.
Last fall term I was obsessed with Jojo's Bizarre Adventure and especially fascinated by the colouring because it goes NUTS - and I even included part of it in my comic project (still not as bonkers as jjba goes but compared to my usual palette, it was). And tbh I had a lot of fun with it. I think finding things/elements that make you excited to try them out helps a long way and can push you a lot. Especially with doing exactly the opposite [insert element you want to experiment with] of what you usually do.
And in the end, by now I only see improvement of my art if I look back 1-2 years or even longer, to partly even thinking that my art got stiff and worse than it used to be. Sometimes, to prove myself that I actually improved I do these "draw this again" memes that used to be hot shit on deviantart like, 6 years ago but I think it actually helps and you can see what points really got better, this can be really surprising sometimes!
There literally never is a glass ceiling, even if you have the feeling of reaching it.