David Ellard has kicked 28 goals in his career, yes I'd trade or delist him. Whether it is this season or next is subject to what is coming back into the club at the time.
I agree he's a year to year proposition but at the moment he's performing a role, as a poor man's Betts. Aside from Menzel, there's no one coming through to play a small-medium goalkicker. If he continues his current form then he, for me, would at least survive into 2015.
If we're particularly active in trade week and could acquire a young small-medium forward cheaply for say a 2nd or 3rd round draft pick (e.g. J Green, D Menzel) then you may have a point of forcing him out.