Agree with Charlie99 need extra glasses for standby and a variety. For variety also you need to understand about your customers, I mean in Thailand normally people don't mind as long as its decent glasses its good enough (many places like Nang Nual the "wine" glasses are so small don't even qualify to be wine glasses). What I really mean is you need to understand your customers whether they mind or not, second it comes back to your wine selection as I understand you are keeping less than 10 type of wine as beer is your main sales so it really doesn't make sense to keep too many types of wine glasses but surely you need to have at least 3 types - for red ; for white ; for champagne.