It is very hard to organise any sort of event involving people coming and going. I think it is rather cheeky to say the least to hijack the existing museum, drinks and meal arrangements. Clearly people can do exactly what they want but it does seem rude to begin changing the arrangements.
Sorry, it's not supposed to be rude, I honestly just find the Watershed Cafe more like a coffee shop than a place for 30 people wanting to have a social event. (just my view though) The tables are small and have 4 seats around them and there are a few benches, so when you throw in a group of 30 on a Saturday at an already busy place it becomes very crowded.
Honestly I don't mean to come across as rude or imposing, Please feel free to google Watershed Cafe and make your own judgement.
The Bars I suggested are big and have plenty of space, I just thought it might give people more of a chance to talk. I don't mind being told to shut up and mind my own business and just go along with the plan, but it was just a suggestion and nothing againts any of the fine work BotB has put in.
BotB - Sorry I did not mean to Hijack your plans, I'm more than happy to chill at the Watershed, I will just have to buy you a beer now !