Can't offer much input on this but as a note 30 minutes commuting will actually put you out quite far. For example I am a 25 minute (slow train) train ride from Streatham to London bridge which by road is approximately 7.5 miles out of the centre of London.
Then again I hear you can pretty much make it from Brighton to the centre of london on one of the fast trains in 30 minutes
Just giving you a bit of food for thought.
Speak to people like Thor, Kate, Jambo, in fact a lot of people here in the SOHO should be able to help.
Benji