Perhaps an intermittent floor basis, instead of permanent, as I understand a permanent floor would be problematic.
I think this should be a good compromise.
For example, you have just achieved a TER of 1601.
Instead of having a permanent floor, you have like 3 months or something where you can't enter tournaments with bandings below 1600,
even if your TER slips down.
This would be to discourage people resigning all of their games in a tourney just so they can drop their rating down to instantly join a lower banded one, like someone just did in my group, someone who has conveniently won several banded tournaments, probably by practicing the same thing!