Well, I also meant that you should release a version without the specific markings for each sub (type VII, VIIC41, VIIC42, or IX).
Just a regular ol' depth meter, mostly similar to the one in your screenshots...
0-150m green
150-250 yellow
250-400 red
I really just love the lighting and the clarity of your gauge. When you release it, I think I will stare at it often...