purple could be genetics or night time temps... or combination of gentics exacerbated by night time temperatures. greater than 68F should avoid it most of the time, if possible. we can't do anything about the genetics and it's potential impact to how efficient photosynthesis is in those areas.
mobile nutrient issue at bottom, looks to be progressing tip-in. N def. if it's been a slow progression you don't need to add much to formula. plants do shed leaves occasionally, too. if it seems isolated, and slow progression, can easily wait and see.
and at top / middle it's interveinal with spots - mg deficiency. give'er a bump too, if you choose.