Are my expectations too high?

I don't thing that is a head gasket problem.

Get a straight edge and some feeler gauges. and find out if it's your heads or the block that has a valley or dip in it.
If they are straight you may want to look at the threads done in the block.........Bolts are two long or there is trash in the bottom of them thread for the head bolts.
You need to know these thing for sure, before you go buying another head gasket thay will probably do the same.
Just my 2 cents.