I think it’s worth pointing out that the majority of XBLIG players will be playing solo, so if the people who have difficulty with your game are those very same lone players, the issue needs serious consideration.

Imagine a Call of Duty, Battlefield or Halo where the developer said “yeah, we know some players have problems, but only the ones who play multiplayer, so we didn’t change it”. That’s the bulk of your market! In XBLIG circles, single player is not only most of the customers but also the majority of the indie press.

We had a couple dozen people playtest the game – all sorts, from Halo junkies to people who had never touched an Xbox controller in their life. Almost everyone had fun, but the players who had the roughest time were the handful of people who had difficulty aiming and were playing single player. It sounds like that was your experience, so I’m not surprised you got frustrated. A reticle and glide path would be a nice set of training wheels, but we didn’t have enough players struggle to that extent with aiming to make it seem worth adding.

I agree, having different types of baddies do different positive things for you when you kneecap them is a strong gameplay idea that came up several times during development. Ultimately, it didn’t fit into our time constraints though, and we had to settle for getting a triple score bonus when you shoot other enemies in the knee. C’est la vie.