You've been improving so much!! I admire your discipline
Wish I had your patience when it comes to painting ahaha !
If you're still looking for good ressources for 3D studies and perspective and spatial awareness, i found this youtube channel that really helped !
The guy is specialized in Industrial design so you can't get more perspective and 3D than that, he has very good educational videos on the basics you should check it out if you have time and feel like you're lacking on that department
keep working hard, thats motivating to see !