Early bird dinners/moderate prix fixes in Vegas?
If you don't have wheels the cab ride might offset the savings, but Rosemary's is definitely worth looking into, especially for lunch.
Their 3-course prix fixe lunch is just a bit over $20, with a 3-course dinner prix fixe @ $45 (some dishes with surcharges).
They do a 5-course tasting menu for less than the $85 you mentioned,
with both wine and beer pairings available with the tab still under a bill.
You could also gorge on a parade of dishes from the small plates menu
served in the bar, have a couple of rounds of drinks and be well under budget, cab ride included.