Just put it at 0db threshold so it's like no limiter.

I do both but instead of a limiter, I use a hard clipper. Sometimes the clipper gets me 50% of the way to the sound I’m looking for.

Depends on the project but in my case where I’m almost always working within heavy genres I tend to have one on my master bus just to check how it punches. I do mix into a mix bus processing though, settings may vary according to the song and production.

Yes. First use the 6 db “trick”, so you have some place left to go when you are done and ready for mastering. As well, you need to know what your limiter sounds like. When you start hearing it…it’s time to dial things back. If not, congestion happens quickly. Top down mixing is used by many experienced and renowned mixers.

If you plan on working with a mastering engineer, the advice I always provide is to leave everything you used for character on but do not use anything solely for the sake of loudness/volume.

No. It's useful to learn to turn everything down anyways.

When tracking, I use a clean master channel, no plugins at all... but that is only due to latency and performance issues. One of the first things I have to do after recording is just move the entire take forward or backward in time a tiny bit to account for these types of thing. For playback, I will put a mastering preset on just to hear how things might sit "in the mix." I listen, make decisions, and then remove the preset and turn the monitor volume back up to compensate (1/2)

I have soft clipper on master

Absolutely. Also distortion, saturation, delay, compression, and - most importantly - twelve reverbs.

Depends. If I start off with the intention to produce something, I usually would have no limiter on. But I often start out my ideas by jamming live. And my “jamming live” template does have some limiting and quick and dirty mastering on it. 😁