Generally I loved it. It is a great game. Controls easily its biggest asset, they are superb!! Graphics are great! Loved the voicework/dialogue which was a first for the series. Corruption/Hypermode also a very good addition.
As for the fetch the energy cells quest I had already begun that earlier on in the game so only had to get one or two at the end, which didnt bother me at all!
Lack of weapons/powerups. I realise its not strictly a FPS but after picking up all the missile powerups/expansions I never realy found my self having to use them! Isn't it missing some powerups from the previous games?
Game does feel a bit short. Maybe its the way it splits up gameplay by going to different planets and backtracking is at a minimal or maybe its the fantastic controls which give you pinpoint accuracy to dispatch the enemy.
Its a great game! All Wii owners should definetly consider it.