Personal experience ....... if you are using cinnamon you want it to finish sweet........ probably really sweet.
Cinnamon with no sweetness = bad (just sprinkle a little ground cinnamon in your hand and taste it, not good alone).
I attempted a beer with cinnamon once (holiday spice ale) and vowed never to attempt a spice beer again after that. It was horrendous.
Best of luck.
Up next: Kolsch, Alpha Squirrel, Tripel rebrew, Witbier
Currently Fermenting: Charlie Sheen (barleywine)
Kegged: Tiger Blood IPA, Irish Red, Strict Observance Tripel
Bottled: Dry Stout, Pliny the ..... Squirrel?, Cream Ale