Hi,
Why does making equippment get boring

? Is it the fact
that you can't seem to be able to figure out how to do it right to make it look good?
In my opinion, you will improve "drastically" - as you wanted it - if you do things that you find boring or very hard to do, things that you'd like to give up at.
Doing simply studies, not fixed images (doodles), will help you with that - I assure you

Doing small things might also turn out to be the hardest thing to do for one, so you'd be better starting with something bigger and heading then
onward to smaller stuff as you should try to get "details" right, in this case, which is only achievable if you do details in bigger things. That's what I think! (=fundamentals)
To get back to the start, and look at your stuff, I think it would be best now, to finish what you once started, and remake your objects.
Take them as reference and make them from scratch.
A teacher of mine once said that you will only improve if you destroy previous works that you have bonds to!
Do a "Before/After" and see the results.