yep definitely if you look back and can see improvement then that's worth its weight in gold. But always remember that no matter how much progress you make, there's always stuff you can improve on, so dont stop improving!!
I think having a job slows most of us artists down, I have my own job which does the same. I don't work a full week but I lose a whole 2 days a week which I always think I could be drawing in. But making the most of your time that you have is for the best, no point complaining about time you dont have
I think it's pretty cool that you can release in Japanese and English, I'd definitely love to do the same at some point with my mega serious works. Do you find you get any interest from Japanese audiences?
I'd take a mega stab in the dark and guess the science explosion intro has something to do with the random shaped characters
oh talking of random shaped characters, I've been reading
Hard-boiled cop and Dolphin and it sort of has similar vibes top your work, maybe check that out for some ideas if you haven't already
all the best and keep it up!
it'll always be a slow start when you're starting from zero but you'll build up an audience soon enough I think if you keep working at it and releasing new chapters. (all the while building up your art and storytelling skills XD)