Don't know just where the problem lies, but I can assure you it isn't a lack of KE. 61# is plenty for anything on four feet. For example, I routinely get complete passthroughs on deer sized game with a setup producing only 39# of KE. But then I shoot a fairly narrow (1 1/8") fixed blade head.

YOu don't mention at what distance your shots are, but with a decently tuned bow your arrows should be flying fairly straight at normal hunting distances. Maybe some fine tuning is in order, but if it were me I'dput the experience to good useand go back to what has worked in the past and be happy.

It sounds like you know how to tune well enough that there shouldn't be much use for using a mechanical head unless you are looking to introduce some problems into the equation.