My university has had no-frills recruitment since the year we transformed from locals to NPC. The year I rushed (the first year of NPC) there were, however, skits on one day. After that year, decorations were more limited, philanthropy day was added in place of the skits, and everything else pretty much stayed the same. The second round party remained a slide show/video day.
As others have said, outfits were not supposed to be "costume-y" or identical. However, you can still coordinate or pick a general color scheme. For example, instead of buying the same GAP red pocket tshirt, members pick their own red tshirt from whichever store/brand they want. The idea behind no-frills rush is to give the PNMs a look at the REAL chapter, which is why they don't want everyone dressing the same. You don't normally dress identically, do you?
Although we were able to have rush themes for the week or each day, decorations at my school were heavily regulated. I think this had more to do with money, since some chapters had more to spend than others. For each day they usually gave us a budget and perameters we needed to follow (ie only two walls decorated, only 200 balloons, etc.). The only day that we could go hog-wild on was preference. There were no rules on decorating for that day, and chapters really went all out. Our rush was held in classrooms (we didn't have houses), but you couldn't tell...we'd cover the walls in black fabric, tablecloth/slip cover all the tables and chairs, and cover the ceiling in balloons with curled, sparkly ribbon hanging down. Flowers were all over. Amazingly, they even let us use candles on the tables. So, you might still be able to decorate!!!
Regarding drink/food, the only stuff we had was water, plus food provided by panhellenic at a snack break between a couple parties in the first round. Since some chapters were worried PNMs would judge chapters on the type of water they offered, panhellenic designated a brand.
We still sang enter and exit songs at the door, so i hope you can. The PNMs love them (though they're startled at first if they're not expecting it), and they sometimes are very helpful when it comes to keeping each sorority straight.
One more regulation we had was regarding alumnae or actives from other collegiate chapters on the rush floor. This may not apply at your campus (and I suspect many), but some chapters on our campus would sometimes enlist the help of collegiates from neighboring chapters if they were afraid there might be more PNMs than actives. It helped them avoid double-rushing, and sometimes gave the PNM a big-picture view of the sorority. Alumnae were sometimes used to communicate with Rho Chis, get more water if needed, or other tasks that might be needed during a party. If a chapter wanted either these collegiates or alumnae on the floor, they were limited to a number set by panhellenic.
Honestly, when I went through rush, I hated watching the skits at each sorority. I thought they were cheesy, and told me nothing about what it was like to actually be a member of that sorority on a daily basis. I would've rather spent the time meeting more members so that I could make decisions on whether I fit in there. No-frills formal rush is really not intended to "entertain" women so much as it is to help them make an informed decision on membership. Instead of focusing on cute dances/lip syncs, they focus on conversation with members. Most of the women on my campus liked the no-frills way - although the rules can be a bit tedious - and couldn't imagine doing it with frills.
Before recruitment is planned, maybe think about meeting with the greek advisor to discuss the really important things you'd like to keep. Try to keep in mind, though, that the no-frills way of recruitment is actually the way NPC wants things done now...the greek advisor is just following the trend.
