So you are basically talking about 7 hours of party for 100 people.
First a caution; as discussed on the beverage planning page, in many states the host is legally liable if a a guest has a DWI accident on the way home from a party or event, even with private parties. What that means is, you should stop serving alcohol at least an hour before the end of the party (maybe when you serve the snack?) and have a coffee service then, dinner coffee service level if you look at my beverage planning page. Protect yourself and your guests.
Your light drinkers will drink 3-4 drinks, so 45x4=180. Your heavy drinkers, 6-7, so 7x45=315. Total, around 495, max.
You have 96+ drinks of each slushie, around 200 total. 3 full kegs at 160 bottles per keg is 480. 48-72 light beer. Total, around 750. I would suggest, too much... 3 pony kegs (1/2 kegs) for a total 240 would be my first suggestion. Wine spritzer is completely unnecessary.
Water is good. Tea is fine. Sodas, you will have left overs, see the beverage planning page for my suggestions on the mix of cola, diet, etc. If you do punch, it will cut down on the soda, but I wouldn't; instead I migh bring a few extra gallons of the slushie lemionade mix, as that is most likely to run out.