The biggest issue for sandy soils will likely be moisture conservation. (It is for our sandy soil anyways) The main thing would be to reduce moisture evaporation through no-till farming practices, build up your organic matter, and remember that every weed is one more plant that is consuming moisture with no economical return. Also, depending on how much rain you get annually; try to grow crops that require less moisture and crops that require the bulk of their moisture early in the year to avoid the added stress from hot July summers. I have no experience with alfalfa, but we grow wheat and sunflowers on all of our land, and I still have seen major crop failures.
strip till.. and spoon feed the N.. i got 4 or 5 circles with organic matter in the 0.7 to 0.9 range. It wont hold water worth a damn but normally is some of my best corn just takes different kind of managment..
I say do no-till and try, try, try to build up the soil as much as you can to help reduce water loss and potential erosion and increase water holding capacity. If you need irrigation, do drip irrigation if possible. It has a lower evaporation rate and water usage. Water is expensive so why let the air take most of it. Also look at the usage history of the land and have soil samples taken. Watch out for salt burn from fertilization and for salt accumulation in the A horizon of your soil with any type of irrigation.