One idea "out there" that I think warrants a look at is the "Stepless Salary Schedule" created by educator Bill Maas. It is in use in several districts in Arizona.
Here's a presentation on it: Web Link
And another, more detailed one: Web Link
Here's a Q&A from the presentation: Web Link
Here's a district's website with more info on it: Web Link
Here's Deer Valley's current stepless salary schedule for certificated staff: Web Link
One benefit to this alternative salary schedule is that there's no employees "frozen", or penalized for being senior staff. I think such a feature would be attractive to employees. It also gives a district more flexibility.
"Under your old system, when you have “lock-ins,” just trying to move everyone down on the salary schedule takes about 2.75% new money. In those years when you don’t have 2.75%, you have no system of distributing the money that you do have. So what it does is gives a system of distributing the funds available regardless of the amount. If you have more money that year than what steps would normally be, you have the same system. If there’s less money, you have a system. Under the existing system, when you have the lock-in steps, it leaves out about 20% employees, who are capped out at the end of the salary schedule. So this prevents that. It gives everybody, on an equitable basis, a portion of the money that’s available."
The Stepless Salary Schedule also lends itself to any merit-based pay system.