200 is a good anount of subs for how many updates you have, and your rating is good! You don’t get many likes or comments tho so you could try putting a little “don’t forget to like/comment, etc” chibi thing at the end? Black and white comics usually take longer to gain subs though.
Also a lot of your screentoning is around the same medium shade so you could try increasing/decreasing the tones to to create more contrast? Honeslty it makes my eyes sleepy to read bc of the lack variety in tone depth