I'm hosting a party for 50. I need a punch, mostly for the ladies (men will be drinking beer) and I'm thinking something with Watermelon Vodka. That says spring to me. Don't want anything too sweet. I'm in South Florida, so watermelon is available here. Any suggestions on what goes into a do-ahead punch?? No champagne, no Pimms, no martinis and don't want to be blendering drinks all day. Need a great punch. Help!!!!!