Delucca is good if you haven't been before - Make sure you are HUNGRY.
Coal Vines in Southlake has been one of our favorite inexpensive date nights. Thursdays half off bottles of Wine and their Chicken Marsala is fantastic and really good prices.
Huge fans of Chez Fabien on Main Street Grapevine. It might be a little pricier than 100 for two but depends on what you have to drink. Their Lobster Grilled Cheese + Lobster Bisque combo is like 29 bucks and I have dreams about it.
Wildwood in Southlake is another good option. Haven't been there in a while but they have been known to have some good specials.
If you're willing to make the drive over to Roanoke, there's a new Restaurant, "Oak & Main" that is fantastic and really good prices. We have been 3 or 4 times in the last month because of the quality and value. Super cute for date night and it's a cute walkable main street that isn't super touristy like Grapevine Main.
Over in Coppell there's J. Macklin's and Victors Wood Grill, both have been good date night places for us that aren't too crazy in prices.
If you go to Fogo de Chao over off of 635 in Coppell, most people don't know you can sit at the bar and get happy hour prices all night on food and drinks. $15 rack of lamb and $10 caipirinha has been one of our favorite date nights where we can feel fancy without dropping $100 plus on the full Brazilian Steakhouse experience. They also give you the sides even if you sit at the bar.
Last, if you haven't been to Weinberg's Deli yet on Main Street Grapevine do yourself a favor and go. Not a fancy date but you can go to Bingham's winery across the street for a glass of wine and then go grab a sandwich. We do it probably 1-2x a month. It's casual and fun and not too expensive.
Welcome to the area!