To make NiceWrench more “gamey” you could have players navigate a level but they have to collect either red or white stars which are always moving in the opposite direction. Players must choose which ones to grab and must be the same color. Perhaps grabbing more of one color changes the abilities when in that colored mode, not sure… as I said earlier, I’m more interested in the experience of it all rather than a challenge.

It reminded me of a flash game, Dolphin Olympics where your character is a dolphin and your goal is to gain speed to jump out of the water, do tricks and collect speed boosts. It’s a great experience because the sense of speed is really fun and you have to position your dolphin for reentry into the water just right or you lose speed. If you make it high enough into the air you get fireworks.
http://www.kongregate.com/games/arawkins/dolphin-olympics-2

You guys (Petri too) give me the willingness to prototype!

The crash was instantaneous, there was no window or anything.

This made me think about how the axes of “intrinsically satisfying core mechanic” and “reward/punishment relationship” (difficulty curve in more conventional terms) intersect. For some games you can change the goals, rewards and punishment significantly, and there’s still a game there… those things are ultimately just excuses to have engage with the core mechanics. So finding another goal – even a simple one – that keeps the game interesting isn’t very hard.

On the flip side, you have something like Etrian Odyssey (a Wizardry-like RPG) or Shiren the Wanderer (a roguelike), both for DS. Normally, RPGs where you level up mindlessly bore me to sleep, but the way those games ratchet up the difficulty makes every decision tactically significant, so you’re not grinding for its own sake so much as grinding to stay alive. Still not the sort of design I’d aspire to, but they’re interesting to contrast with something like Nicewrench, in a (1, 1) to (-1, -1) sort of relationship along those axes.