Thank you for the kind words @RicardoAndrade and sorry for the delay in replying. The Math Educators private beta takes up almost all my SE tiime.

I am not completely decided, but what I am pretty sure about is that in addtion to not retagging the one that have a topology tag, I will not retag (most) of those that have some fitting top level tag (other then the topology ones) and a "topological" tag, something like gr.group-theory topological-groups topology I would simple leave this.

In addition there are some question I think are not worth retagging, actually I think some would best simply be deleted completely. I am not sure how to go about this yet.

I wanted to compile a list of unclear cases at some point but did not yet complete it.

For above mentioned beta, and some other things I did not do anything lately but should pick it up again soon.