Flagship Brewing
If you and your date like beer, check out Flagship. They make great beers and have a really nice taproom in which to drink them. If you're someone who likes a casual vibe on a first date this definitely fits the bill. Also highly recommended for weekend daytime meetups. Only bummer is they're closed on Mondays.
It's a brewery, so beer.
They don't serve food, but if the date's going well we'd recommend ordering a pizza (they encourage you to bring food in).
Pleantiful picnic table seating.