I think they should be paid what the free market decides. Get government out of the schools... they've turned them to rot. Let the teachers negotiate their contracts indiviudally. Let poor schools and teachers fail and find other management or jobs. If it's 100G... in the private sector... fine! But there aren't many worth that much.
We had a better education system before the DoE and unionized teachers. No wonder. If you couldn't cut it you found other work or got your act together. If a teacher of 15-years is mediocre, there is no way this individual should be paid the same as an exceptional educator of 5 or 6-years.
If I'm running a school, you can bet I'll know the performance of the teachers and act accordingly. The lower rung teachers I would be looking to replace with better talent, until I had a lineup I knew was giving the kids a solid grounding. If each school did that, watch the standards jump. You can be sure other schools would be seeking my talent too. But I'd be sure to have a environment where the teachers and students could excel. If another school bought one or more away, good for them.
We need that brought into the education system. Instead we have the dry rot and too high costs unionization brings.