Where, who is moving faster and have more energy ? it all can be set on server side, both speed and energy consumption but I still don't know what/where you mean :)
CW? - UI makes game better somehow ? You can always change style and colors in your game/user settings but is it really important.
CW is much slower and limited, not faster unless you change settings on server side. You can't wall jump there (uless you're using mod which is not as good) or use some useful glitches. You can play CW in this network: http://cryserv.eu/
but there are not many players - even less than 20% there than here. Besides Crysis 1 is really much better MP to have fun with.
If you want to play some Crysis Instant Action - you can send me private message at www.crysis1.com and we will set some meetings even during the week in the evenings. No problem. Depends ONLY on you.