1. Right. The OP didn't mention those things.OP never mentioned wanting to change tonal character, nor was "early breakup" mentioned. I have no idea why that is always the goal. I can't be alone in enjoying a sweet-sounding, clean toned amplifier with character.
2. It was a suggestion, since the OP said the amp didn't get breakup until 9 or 10 on the volume. The OP then said no, it's fine as-is.
3. I like exactly what you like, especially with my Tremolux. I also like being able to get a fatter tone without having to explain it to the police at the door.
4. It's all good.