When replacing sulfur with candy in the Naga banks, did you ask many people? They grumbled a bit and got used to it. Bugs need to be addressed critically, without considering public opinion. In the worst case, leave a checkbox option during generation so that people don't complain too much.
Added 9 minutes later
A portal is a connection between two zones, an alternative to a simple passage and entrance/exit from a dungeon. Therefore, if this is not intended by the map creator (and randomness cannot think by definition), portals should only be two-way.