I'm not the most highbrow person and I tend to slum it up a bit so you may want to take the following with a grain of salt. And a shot of penicillin. But at least the places are priced reasonable.
As a local I try to avoid the strip like the plague so here are some off strip places (there might even be a few chain restaurants in here):
The Kitchen Table in Henderson (near DragonRidge Country Club)
The best I can describe this place is Mexican food cooked in a French way? The wait to get in can get long so I'd suggest calling ahead.
Really just for the pancakes. Ifin' ya like pancakes.
Massive stuffed crepes and various flavors of mimosas. Can't recommend this place enough. Seriously.
Truffles N Bacon Cafe
They ain't jokin about that name.
There are tons of places of high quality to choose from but I really like this slightly dive place. They have another location but it's not as fun. There's no other way to say it so I'm just going to say it; I highly recommend having a man whore and a wet dream here. Don't worry, they're just rolls. At least at this place. What you do in Vegas on your own time is your own business. If you go here and there's a long wait, don't worry. There's a serious dive casino next door called Dotty's that sells bottles of Stella for $2.50 per while you wait. OR at least they did a few weeks ago when I last went.
Taco Y Taco
About as close as it gets to a taqueria in Mexico. Fantastic tacos and a great selection of hard to find mezcals.
Frank & Finas Cocina
Okay, this one is not what people expect. You could pick this place up and drop it anywhere in Mexico and nobody would know it wasn't from there. Authentic is probably the best word. Second best mole I've ever had. (The first being at Cafe des Artistes in Puerto Vallarta.)
Due & Proper
Just a fun place with a good beer/drink selection and a good mixed crowd. Also, tater tots with truffle oil, bacon, and cheddar.
Best old fashioned in town although they call it a Winston Churchill.
Double Helix Wine & Whiskey Lounge
Horrible selection of wine. Don't go here for the wine. Go for the whiskey and mezcal flights and a cigar.
aka: Cougar Central But seriously, they do have good martinis and not bad prices during happy hour. Near Double Helix in Town Square.
Milkshakes with alcohol located 108 stories up. Cocospresso Shake: Vanilla Ice Cream blended with Malibu Rum, RumChata, Kahlua, and Espresso garnished with a mini donut.
If I think of anything else I'll post it.