Or just change these ifconfig lines to airmon-ng start wlan0 Personal I never had problems using wifite.py when putting into monitor mode, I don't use it a lot though but if you say its a bit ropey this would probably a better solution than letting wifite.py do the job.

edit: Forgot to say I like the way you disabled WPA-Attack as you won't come any further with WPA on a phone, except the handshake capture :P WEP is doing great on the N900