Regardless of their pay, a congressperson will be tempted to align their incentives with service to causes other than their electorate. Plus, people who just want to make a lot of money (instead of serve their country) would be tempted to run for congress to receive "football coach level pay".

It makes sense to pay them a high enough wage so (lack of) money doesn't become a worry in their life, but incentives get borked beyond that.

What worries me more is the fact that they are guaranteed that same wage for the rest of their life after serving in Congress.