I won't be able to attend but as a Liverpool resident I can make a suggestion for a meeting place - The Bluecoat Chambers.
NOT the café on the ground floor, the restaurant on the first floor is much nicer. It never gets busy, its reasonably priced and the food is very good (although its only a small menu it does cater for all tastes). There is also plenty of room for a large group.
The Bluecoat Chambers is a great place to visit, very much a hidden gem in the very centre of Liverpool.