I'm not sure LCY is more relaxed .... there's nothing relaxing about it
Irrespective, I'd rather spend 45mins waiting at LCY before being airborne, as opposed to having to fight my way across London for over an hour+,
only then to be at either of the LHR/LGW zoos. If you want to define that transit process as being in any way relaxing, that's your call.
Also, the OP is only FIVE MINUTES away from LCY. For myself, that would instantly be a case of "decision made". However, as a previous poster said, you pays yer money ... etc.