Note Performer does not always have the most sophisticated sounds (I'm not crazy about their strings) but by and large it manages to represent the relative balance of the various instruments and groups.
Apart from Garritan and Noteperformer, I don't think that any other sample libraries provide the 'coupling' for their products to work 'well and easily' with Finale. I could be wrong. (E.g. which Key Switch and MIDI CC does what.)
I'm sure that other people may have done the work, and shared their templates on various forums.
I'm not understanding the problem. I use many different libraries in Finale without a problem. Aria, UVI, SampleTank4, Kontakt are four of many Players that work well and easily — once you know your way around Score Manager, that is.
I'm not a big fan of Note Performer but, for down and dirty, it's ok.
It's not so much the players, as the libraries. Do the libraries work out of the box, applying staccatos, trills, dynamics and everything? Surely if they use different key switches and CCs from Garritan, then you'll need to redefine everything in Finale?