Here is the actual link to the royal offer.
Code:
https://www.mlife.com/en/offers/royal-offer.html
Took a minute to find it. I always thought the MGM offered the most bank for the buck. I think it would be possible to make 2 different reservations to get double the resort credit then combine them when checking in allowing you to pay just once for the room total in order to take advantage of the amex $50 back on $250 offer. Note the offer only require that you put down a deposit. Also the offer require a two day minimum stay.
As for other tips, definitely check out a cirque show. Ka at the MGM and Mystere over at TI are my favorites. Might be able to score some discounted tickets with tickets4tonight or some other method. If you have status matched to MGM gold there is an offer in your mgm account that gives discounted Cirque tickets.
Food on the strip is really expensive and not necessarily that great. I used a groupon and got a good offer for an Italian place on the strip. Visit in-n-out, there is one right off the strip. Look for some food reviews for restaurants off of the strip. One of my favorite places to go is the Ellis Island brewery. Probably some of the best value in Micro beer, pizza, and bbq anywhere near the strip.
If you are into hiking and/or climbing. Red rocks is a 30 minute drive from the strip and it is beautiful with lots of great hiking options. I visited with my pregnant wife and we hiked every day for the 4 days we were in vegas.
If you have never been , the Grand Canyon is worth the drive if you have the time. The Hoover Dam is really interesting also.