No, it wouldn't be appropriate to say this if you were already working in London. The meaning you would seem to be trying to convey if you were to use this in such a situation would be similar to 'I enjoy working in London.'
Then can we say 'I'd be interested in hearing what you think' or just 'I'm interested in hearing what you think'?
Yes we can say either. The first is politer as the remote form doesn't put so much pressure on the listener to answer.