As for field smoothness, yes, that is an issue.  But there are less-destructive methods available than plowing.  And once you get it perfectly smooth for alfalfa, what will be the answer when it is time to rotate away from alfalfa?  Will you again say it is too rough, and simply must be plowed? 

In one word, "yes." 

In many cases, it might not be plowed, but it will be gone over with a chisel plow or ripper and disc'ed, which doesn't qualify as "no-till."

One very large difference I've noticed between midwest annual-crop farming and western alfalfa/grass production is our high populations of:

1. Pocket gophers.

2. Ground squirrels (esp. the Belding ground squirrel, an "import" from California).

3. Meadow voles.

With the exception of the Belding ground squirrels, all of our vertibrate pests are natives here, and exist in the millions of acres of BLM ground around here. You can control pests all you like, but the job is never done. And in lean years, or when the populations get too high on BLM ground, the pests flood onto alfalfa fields in waves. 

Then there are predators that come in after these pests, namely badgers and foxes. These "helpers" are often worse that no help at all, because while a squirrel mound can take out the rear window of your tractor if you're using a pull-behind rotary mower/conditioner, you can practically roll a tractor over when you cave in a badger hole here. I've buried a baler wheel into a fox den and had to walk up to the shop, get the backhoe and chains and lift the baler out of the hole, fill it in and let the baler back down. Betcha don't see that too often in the midwest, just like you never see drain tile put into the ground out here.

All of these animals will rough up an alfalfa field here in five years something awful. Rough hay fields means dirt and dust in the hay, broken equipment (especially NH bale wagons) and uneven water application. The only way to get the field smooth again is to collapse those holes/dens in the ground and get the soil to settle back down again. Ain't no other way that I've figured out, and there hasn't been anything discovered in 40+ years by the old timers, either. The guys who are able to make no-till work the best here are surrounded by sagebrush or they're BTO's who are their own neighbor -- ie, there is no other land around them but their other fields, and they're able to keep the pest populations down on their interior fields, but they still have to occasionally till their outside fields that border the BLM or a deadbeat neighbor, most often a residential neighbor.