I use Obsidian too after i met with lots of failures using the default SC rules. Obsidian to me is very clean, fast, intuitive, and it engages the players creatively, and myself as well, without having to memorize a page or two of skill descriptions. What i've been doing is having three possible outcomes for a challenge based on failure, partial victory, and full victory, with the players knowing the stakes from the outset. Works well enough for me. Although i still like to sprinkle healing surge loss and possible combat as options, but i do agree that having a more emotional impact for success or failure is the best way to go.