New here so hopefully not a silly question but is WU not the most accurate thing to look at to determine your true Hash speed with the pool you are on?

I noticed before the server upgrade my WU was steady at 2,250 and now its been steady at 1,965.  Maybe since the server upgrade I need to tweak my Config?  Just not really sure what to tweak..   And I use to get zero rejects now I have like 2.35%(Which I assume is not bad)

Thanks!