Too much stretching?

Maybe a little bit stratched, need light closer. When transplantinng i usually plant it deeper and i cover 1st and 2nd node for stability and to get rid of any stratching.

Yes, you can have T5 flouro lights as close as 2 inches. Half filled tiny cups are going to reduce growth immediately.

Yes

It's a little stretchy but you got room in your cup to top off.