I pronounce it with more of an S than
Elizabeth. It kind of sounds like
Alyssa Beth. I prefer it spelled with the Z, but if you want the nickname
Elise, then
Elisabeth makes more sense.
I think
Elisabeth would go best with a more uncommon middle name since it's so common and plain (but still pretty!). I quickly perused some name lists and here are some somewhat random suggestions:
Elisabeth AugustaElisabeth CarolineElisabeth ConstanceElisabeth DarcyElisabeth DelilahElisabeth DorothyElisabeth GeorgiaElisabeth GretchenElisabeth JacquelineElisabeth MeganElisabeth NolaElisabeth OpheliaElisabeth PaigeElisabeth RamonaElisabeth RowenaElisabeth ScarletElisabeth ValerieElisabeth Virginia