Jens, you mentioned using your stock fins. I have done the same, in my small board, during the last two sessions. Haven’t had any weed problems so I think we are past that for the rest of the winter. A “pointer” fin may still catch a few weeds but regular wave fins seem fine now.
I don’t have a very small weed-wave fin so it helps being able to use a small regular fin when sailing small sails.