With #1 and #2, you are right when you suggest that formality might be significant. #1 is an informal context; #2, formal.
#3 is not a well-formed question. However, I think the question-setter wants you to compare and consider the meanings of "also" and "in addition to".
With #5, I would accept both answers; but "eventually" is possibly more expressive of weariness, in such contexts. (Or perhaps its polysyllabic nature permits the expression of greater weariness.)
What do you think about #4?
Student or Learner