While I have no objects to the option of more sounds, I feel like the current behavior might not be that different from what you get in actual Lemmings 1? I don't remember for sure. Lemmings 1 (at least on some ports like Amiga) definitely have sound effects for changing the RR, but that's technically not the same as merely clicking the RR buttons. I want to say pausing never played a sound in Lemmings 1, but I could've just misremembered (after all, usually when I pause, I'm focus on some parts of the level and not the sound effects).