I started teaching a few days ago, I did it because I wanted to give back for all the classes I've been to in SL. This will surely reduce the amount of classes and quality classes. But having said that Lindens should still try to encourage education in the system even if it doesn't involve paying teachers.
From TuI and ASL I've heard that they will still try to make classes free out of the kindness of their hearts. Therefore I suggest the following:
1. Griefers. More control to the universities and teachers to handle Griefers that purposely disrupt classes.
2. Better class environments. Help try to reduce the lag at the schools, I'm sure you can provide better machines that can help reduce the lag to classes.
3. Access to Linden help. There are still teachers out there that love to teach. I hope that I'm one of them. But help us maybe special access to help with scripting or special lessons for us teachers to help us provide better classes to everyone. Doesn't have to be a large amount of time but some time to help us. (We want to learn as well!)
4. I would think for a reasonably complex class it could take 3-4 hours of a teachers time in preparation, then uploading of textures, etc... Maybe provide a subsidy on texture uploads for classes, or even consider paying instructors money for new class courses. This would encourage some diversity in the classes. I've uploaded a few $100L for classes already it just wouldn't sit right with me that I'm paying to help create a class for students.
Besides item 4 which requires continual money being churned out the other 3 items would help me at least come to grips with all the time I've spent creating and teaching classes.
Hope this gets heard....