Our Butler, Glenn, was okay. We didn't ask much of him, but what we did ask he did well. However, he did nothing much proactive, either. For example, champaign icer was removed after first day and our bottle of champaign just left standing on counter (he could have offered to re-chill the bottle on another night or see if we preferred to exchange for a bottle of wine. Never offered to serve us dinner from a specialty restaurant in the suite. Never asked if we wanted a coffee machine (or kettle) in the suite. Small things, yes, and we certainly could have asked for these things, I'm sure, but in my experiences on Azamara and Regent our butlers were always much more proactive in finding ways to assist us.
OTOH, our room attendant, Jay, was top-notch in every way.