Did you ever play Lass with Cleffa? The combo was devastating!
Now, Pokemon Center and Item Finder were nice...but it really sucked pulling those as your rares. Same goes with Special Darkness and Metal Energies before the basics were out...when else do you pray that your rare is an energy?
I don't understand why Spinda is a bad rare. Since when is a (free) energy removal a bad card. Plus it forces your opponent to unown g their active and then you suprisingly pull out your damage counter snipers!
All you really do with Spinda SV is plop a Rainbow Energy and just discard energies with him. (Making him go well with Garchomp, yes.)
Realistically, there will always be one or two bad rares in the set. Granted, SV declined greatly in quality from RR (which was sorta bad to begin with, save for a few things), but there is always a good and effective way to use the 'bad' rares. In Spinda's case, I just named it.