I tried city of love, ukadultzone and 22burlington for a month or two. Nothing much came from any of them.
I was thinking more of London Escort Guide, London Independents, Massage Republic - I've had a few from City of Love too but nothing happens overnight. There's also Tryst, which I don't use but seems to have a lot of the Twitter set.
AW verification doesn't really give any assurance that anybody is genuine (since the profiles can be sold and swapped in a nanosecond - we've removed enough posts from here trying to do so), but yes, some punters are dumb enough to think it will. And Adultwork is by and large where the dumb punters hang out
Leaving all that aside (and so we don't wind up with another WTA thread), do you have a blog and plenty of pictures online; are your working hours/days restrictive and do you offer incalls? There are lots of things that can reduce the amount of bookings you get, even if some of them you can't do anything about.