First time grow/closet. 400w hps. Open to advice & constructive criticism

thanks guys, am looking forward to my next grow now that ive learned a bit from experience. hopefully avoid some of the snags i encountered this time..and maybe upgrade my room a little bit.

First 6 harvested..roughly 815g wet from them... box with lighter is from 3 williams wonder..big bud is off og kush/widow cola, very dense 90g wet. last 2 are the mother of berries that still have a bit of time to go but looking quite nice if i may say so.