Nope.

There isn't really. As long as all of the comments are helpful and not too chatty, and otherwise in keeping with the purpose of comments, we don't want to limit it. New helpful comments are always encouraged. Why would limit how helpful a user can be?

As for editing, the system allows users with 2,000+ reputation to edit as often as they want. Users with less than this amount of reputation can submit suggested edits, and have up to 5 pending from that user at a time.

Site policy is also to have, roughly, no more than 5 of the 15 most recently active questions to have been edited by a single user, although exceptions are made for when e.g. the community is doing a mass cleanup.

Nope.

There isn't really. As long as all of the comments are helpful and not too chatty, and otherwise in keeping with the purpose of comments, we don't want to limit it. New helpful comments are always encouraged. Why would we want to limit how helpful a user can be?

As for editing, the system allows users with 2,000+ reputation to edit as often as they want. Users with less than this amount of reputation can submit suggested edits, and have up to 5 pending from that user at a time.

Site policy is also to have, roughly, no more than 5 of the 15 most recently active questions to have been edited by a single user, although exceptions are made for when e.g. the community is doing a mass cleanup.