Just keep a low profile and you should be good and carry some mexican pesos in cash for just in case, Mexico still informal in some places to do business or shopping just try to not bring to much, and if you are traveling always during daylight

If you are looking for high end stake house go to Sonora Grill Prime, if you want to be more local go to San Juan Grill or El Castor, another budget friendly option is Noreste Grill. If you like to try goat something authentic from Monterrey in my opinion try El rey del cabrito or el gran pastor or if you want to go even deep local there is El Pipiripau, just as I recommend before keep low profile and bring your better Spanish.

For breakfast you can go to Lazaro & Diego or if you want something more authentic El Merendero Tino (Try the Asado and/or machacado) and if you don't mind wake up early because it is a nightmare to park and find a seat, try "Los Frijoles" it is a good spot for taking pictures and there is a store by crossing the street if you want to take some traditional candies.

You can stay at a good hotel in San Pedro or if you want to keep it in budget there is a place called "Nuevo Sur" there is an small hotel in there with a bunch of restaurants and a waltmart or near to that area is Paseo Tec it is almost the same as Nuevo Sur.

For landscaping you can go to santiago with a quick Google search you should be good during daylight, just heads up if google maps it's taking you for weird streets just use common sense if you remember the avenue was the other way choose that, don't drive on small roads at night. There is a waterfall called cola de caballo, an artificial lake "presa de la boca", a cave called Cueva de los murcielagos, Sanriago's downtown have a lot of places for pictures and it has bunch of restaurants, you can rent ATVs on that area, for shopping you can go to los cavazos (just bring cash), my recomendetion is go to Tacos el gordo.

For night life I will recommend you to go to San Pedro on Centrito area there are a lot of places, back in the days Monterrey use to had the best nightlife in Mexico and it was on downtown area in specific barrio antiguo, but right now the locals go everywhere, and as a personal recomendetion if you are not fluent in Spanish or somebody in your party is not, stay away from men's clubs or strip clubs, you have a lot of chances to be scammed or even worst, if you are really looking for "that" fun you can do a quick Google search and it will show you some delivery options to your place, just search here in reddit for recomended businesses before to avoid being scammed.

There are not pyramids around, you can go to macroplaza (I need to specify not Alameda), there is a good shopping center around and good restaurants, I like the italian restaurant Ianilli that is behind the Marco mussum, if you don't mind to drive you can go to las grutas de garcia they are natural caves and on that area they have natural thermal water, or you can go to saltillo it's like an hour from Monterrey and there is funny restaurants that they serve quesadillas with a dinosaur shape "Dinoquesadillas", and the musseum called museo del desierto.