There is a nice feature in Project Editor called Comments.

Can we have different types of project comments, which can be filtered too?

So in Comments, we would have comments, to-dos, queries, information, notes, ... something like these.

There would be a filter to see only one or two or more types.

Comments would be straightforward comments like we have now.

ToDo would be tasks which can marked as open, completed, or in progress

queries would be questions which can be marked answered, and then the response connected to them, or they can be open or in progress

Information and notes can be like comments only.