Not exactly a “reward,” but something that could help keep reviewers interested — could we have an option to set a list of 5–10 keywords and not receive nominations containing those (like “memorial” or “plaque”)? Either don’t pick them from the queue at all, or pick and automatically skip them.
I don’t mind if other reviewers want to accept “memorial plaques,” reject them, or vote 
/ 
(whatever that means), or if submitters end up wasting an appeal on them later. Automatically excluding certain things would just save time 