Interesting series of problems

(1) This plant has the tips of the top leaves eaten off. I believe it has thrips, could they do that?
(2) Along those same lines, this is why I believe it has thrips. Does everyone else agree?
(3) I have no idea what is wrong with this one. The stems are very purple and there are all kinds of discolored spots. Any ideas based on how it looks?
(4) This one was just planted after the thrip breakout. Could they have caused this or do you think it is something else?

To avoid confusion I numbered them. Thank you all for any help! Sorry to bombard one post with so many questions.

most likely cause of the majority of this is PH is off, way off. probably thrips too, you should be able to see mites or thrips or aphids with a little searching.