Yes...the front lounge of the restaurant is first come first serve and they offer full bar and wine list, their dessert menu and appetizer service in REALLY comfortable chairs.
The NR Lounge offers the entire menu, not just the abbreviated one on the tables. Just ask your server to see the full menu when you are seated.
As for grown up ways to enjoy the parks:
You can still be first at the gates, just make sure you get the DL early for breakfast at Carnation Cafe! Meet Oscar and people watch as families arrive in the park.
Trader Sam's at the DLH
Breakfast or dinner at Steakhouse 55
Eating beignets and watching fireworks from the Jazz Kitchen Express or eating on the balcony of the Jazz Kitchen and watching fireworks in DtD
Swing Dancing at the Royal Swing Ball at PFF on Saturday nights (also dancing at TLT and sometimes in DtD)
Carthay Circle Lounge -- enjoy a cocktail and the yummy lounge menu
WOC meal at CCR or a F! meal at BB -- you'll have much more flexibility not having to worry about kids
Take the time to chat with CMs and get to know them. We've had great conversations with CMs about why they love Disney and where they are from.
The tour suggestion is great!
Get your favorite treats, find a prime bench at the Hub, and people watch!
Ride your favorite rides (the ones that are open) and take the time to notice and appreciate the details. Ask CMs in line what little details you can look for.
Disney parks have so much live music! Check the daily schedule to find out who will be playing and where. The jazz bands in DL and DCA, the Dapper Dans, Five and Dime, the Ellis Island Boys (fantastic!), the Mariachi Divas (Grammy winners!) -- you can see so many great musicians without any additional fee.
Have a wonderful trip!