Timer too close after tool change - running happy hare (reproducible)

Refer to Timer too close for reason of this error. According to my experience, this “flooding” scenario is by far the least frequent issue and the rest are local issues in the setup that indeed needs to be fixed.
So, as long as you do not know the root cause / circumstances of this error, this generic statements are quite pointless.

Maybe. As I said, this would be on a developer to judge.
In my view, this command is meant to persist states accross the reboot of a printer. Using it and its associated IO impact to manage runtime states seems inefficient and a misuse of its original intent.
Also compare to Save/Restore state for G-Code moves, which indeed is intended to manage runtime states.