There are different rules for different people.
This is so simple to avoid. Don't do it. Wasn't that easy? But since you already have done it, how do you react when the disparities come out, and they will. Don't deny them. Explain that at different points in the history of the company you had different policies, and some of the more senior employees have different work or benefits rules.
That actually is OK, as long as you were fair and equal at the time that each employee was hired. You can land in a five foot pool of trouble if your employees see a pattern of discrimination or unfairness based on
- Sexual Orientation
- National Origin
- Disability Status
Balance your workload evenly among all workers. Assigning overtime to one or two people will breed unhappiness. You can give your best employees more opportunities to earn, but make sure that you have a valid employee review system detailing why one employee deserves greater opportunity than another.
Wait a minute, you say. You have some employees that deserve more because they do more for the business. Actually, I hope you do. But the fair way to reward them is with higher pay, not by creating a convoluted benefits program.
In today's litigious society, if you do something that appears to be unfair, even though it may not be, then you will, at some point, be asked to justify the unfairness. Win or lose, your time and aggravation will make you a loser. Keep all of your employees on the same benefits program and you will have less grief. By the way, that doesn't apply to you as an owner. You can have a different program, giving stronger benefits to yourself and any family if they work for you. If you have one key manager, it's OK to include him/her in the key program, but don't extend it too far down the chain.
If you have side deals with employees, ask yourself what happens when the rest of the employees learn about it. Don't ever believe that it will remain private. If you can't answer the question easily, then work to remove the program. Maybe you have to give a larger raise to someone and eliminate the special program. It will move an expense to the fixed column and raise o/t costs, but this is still better than a potential disuption in the work force.
Keep your employees happy, and you will have happy customers. If you have unhappy employees, for any reason, this will hurt your business more than any recession or competitor.