Far too obtuse, and some of them just don't work. No way tutu fits in its group, the name group is just contrived, no way anyone's going to work it out unless they start out looking for names. And others are like cryptic crossword clues without any template or word length which can only be grouped if and when you've solved them all.

Very hard. I agree with Ace, some of these are just too obscure.

I think the numbers groups could work if you changed "Tutu" to "As well or overly much" meaning 'too' which would give you: too, fore, ate, nein.

I liked the professions group.

I found the male name group very confusing - one of your explanations seems to not even relate to any of the answers "Dan- level or writer"

I like the letter group concept, but perhaps the clues could be easier: "The English drink" for T(ea) maybe, "Old Flame or Roman 10" for (e)X, "A sting in the tail" for B(ee), "Form an orderly one" for Q(ueue)

I hope this doesn't sound too meddlesome. Just my thoughts. I liked the concept.