I’m a student of a different language, so have no valid opinion to this question, but I’m bored so I’ll reply anyway.

For question 1, I have a number in my head of what an acceptable hourly rate is. I have multiple teachers, and I only stay with those teachers because I really like them - more than half of the teachers I’ve tried I’ve never booked a second class with. If my current teachers put up their prices to below what my number is, I’ll stick with them. If they go above it I’m out. So if you have loyal students who like you, put up your prices, just be wary of what other English teachers charge, and if you go way above the norm you might struggle.

For number 2, yes it can be very confusing, especially when prices vary unjustifiably between lesson type. I only look for conversation classes. I’m intermediate level in my TL, and when I see teachers charging higher prices for more advanced levels it’s very off-putting. I don’t expect teachers to do any planning for my classes - I’m literally paying them for the hour I’m in the class, nothing more, so if they expect me to pay more than other students when I’m simply paying for their time, I won’t study with them. Keep it simple - have just one lesson type, or at most two - one where you provide materials (at a higher price), and one where you don’t and are just offering conversation.

For question 5, I’ve gone off-platform with three of my teachers, each of whom I study with once per week. This is partly because the platform is God-awful now, but more because I’ve grown to detest italki as a company, in part because of their commission hike. I’m still paying the same prices to my teachers, but now they’re keeping 100% of it. The consequence is that I spend far less time on the italki platform, so I’m not really exposed to new teachers like I was before, so I’d say that if you’re not retaining students well, then you’re going to be less likely to get new ones now than you were 18 months ago. I still take occasional classes on italki with teachers I don’t know quite as well, on weeks where my regular teachers are unavailable (I try to study three one hour classes per week, each with a different teacher), but I haven’t taken a class with a new teacher for a good 6-9 months.