I have fallen in love with the slowcooker since having DD and it would be great in that type of situation. You can put it on several hours before and do some side dishes like cold rice dishes or pasta salads. Or just rice in the rice cooker.

One of my favourite side dishes for gatherings is a pesto pasta salad as it is filling and tasty. Another i use often is a cous cous salad ( i throw in cherry tomatoes, parsley, mint, slivered almonds, pinenuts, fetta, etc). I do these often at bbq's a few hours before people come and put them in fridge.

You could also do arancini balls (sorry about spelling). Risotto (I make it the day before) and then shaped in a ball rolled in bread crumbs and deep fried. Serve cold (or hot) with a napoli or salsa.

I prepared the pesto salad and arancini balls at my wedding party which i self catered. Just fried up the balls in the morning.

Have fun.