Take a lovely walk in the park with a cup of locally roasted java in hand
Coffee is the perfect first date drink. We shouldn't need to explain this, but just in case: if you are actually looking to DATE someone, and not just hook up, it might be better to get to know them over non-intoxicants. For some of the best in town, hit up local coffeehouse Sunrise Coffee for an excellent pour-over made from their own Mothership Coffee beans sourced from single-origin organic Fair Trade micro co-ops (that's coffee-talk for real, real good), then cross the street to Sunset Park for a stroll along the pond filled with geese and ducks and swans (romantic if you suppress thoughts of all the bird droppings), or through the ancient dunes that once covered all of Las Vegas (the dune field is all that remains of them).
Have super-casual happy hour drinks by the fire pits
Double Helix Wine & Whiskey Lounge is kind of the ideal date spot: centrally located from most corners of the Las Vegas Valley, right off the I-15/215 interchange, on the Strip without being on the Strip, in a neutral location with tons of free parking, good food, and drinks all around, a stellar happy hour to keep it cheap, and a great patio with comfy couches and warm fire pits. It might be a little clichéd for anyone who has lived and dated in Vegas for a while, but it's a solid go-to.