I don't know what else you have in your wardrobe. I'd either:
a) Swap the trousers and shoes out for something more classic (Oxford shoes, tan or grey trousers). You'll be well dressed but the right side of dandy.
b) Drop the tie and PS, and accept it's a bit louche but for you to judge if this is in keeping with the crowd and how you want to be judged
The only caveat - you mention this is central. There is quite a different feel between different areas of London which might be defined as central. The precise area, and your knowledge of the hosts, should inform your decision on what to wear.