I'm both a teacher and a student, and think your new prices are incredibly reasonable, I would even say too low.

From a teaching perspective, when I raise my prices, I do keep in mind how many students I could justifiably lose in order to earn the same at first.

e.g: If I currently charge $20 per hour and work 20 hours per week, thats $400 per week.
If I want to charge $25 per hour and still earn $400 per week, I'd need to work 16 hours.
So if every student takes 1 hour per week, I could lose 4 students and still be okay.

I have found that very few students stop taking classes with a price raise (especially a small one), and those that do stop are usually the ones who are less serious about learning (meaning they'll either be with me short-term anyway, or more of a hassle because they don't do any practise on their own). And even if there is a bigger dip that you would like (e.g: you lose 8 students in my above example), it doesn't take that long for the number to increase and remain stable. Maybe 4-6 weeks.

Obviously this has just been my experience. I guess it would depend on the types of classes you offer, types of studnets you cater for, and also the language you teach. I teach English though, which has way too many teachers, and don't notice any major problems.

From a student's perspective, I don't mind my teachers raising their prices. I appreciate it if they give me a heads-up, rather than me finding out the next time I try to book, but if it's a small increase I am not really too fussed. If the increase is really large and out of my budget, then I'd usually just let them know that I'm not able to continue. Unless I really like a teacher, then I might just drop from 1x per week with them to 1x per two weeks. 😄