Personally, I feel like scenarios have potential but they just aren't there yet. Some of them totally missed the entire time vs money aspect, and really there's no point in running them except to just "see them" (in my opinion). I'm assuming the problem Blizzard has is, trying to balance them to be good enough but not as good as dungeons. Or people would never run dungeons.
I think Blizzard should scrap scenarios completely for level 90 characters, or create a "heroic" scenario that is similar to Brawlers guild for 3 man groups (some trash then hard boss). Scenarios would be a perfect addition to leveling and help with some story aspects that people skip over completely now because they run dungeons.