Lots of old heroes were partially created from the forums, and probably lots of the new hero's skills were based of various suggs (or so I think). The clearest example would be Puck, who was created combining 2 heroes from a DA contest.
I don't think the "only one person" issue is a problem, because lots of implemented suggs were made by single persons. Lots of them were later improved thanks to feedback, but the initial idea and final presentation is still from a single person.
In any case, the discussion focus here shouldn't be about Ice implementing "our" stuff, but simply trying to make a better game for the enjoyment of us all