I think there is a way to simplify the process of selecting which maps you like and which you don’t in the prefered map system: Splitting the selection between mode and map, such that you can downvote a whole mode say confrontation and the downvote applies to all maps of that mode. Also you could upvote a specific map say forest and this would count as upvoting for all modes on that map.
There obviously might need to be some thought on if mode or map has priority in case you have downvoted in one and upvoted in the other. It probably makes most sense for the mode to have priority, but they could also possible cancel each other out.
I think this would make the map preference system way easier to navigate and use as a player, even if it may loose a little bit of fine tuning you can do.