I had an opponent who had anti slip stuff added to his bases and they rode higher on the mat. made it hard to tell if he actually hit an asteroid a couple of times since the corners rode higher than the token. other than that, I haven't seen a prob with templates.

M10 washers fit nicely into the cavity of a medium base.

Sideway view trying to show how little the studs protrude under the base. You can slide maybe a thin envelope under the base.