There's an art to assembling a buffet. It's always going to look a little haphazard, but with a few tricks, that chaos can appear cool instead of careless. A good buffet functions as if there is a mother hovering in the wings telling eat diner how to compose his plate. A bossy mother. In other words, you want to line things up in the order you want them plated, in descending order from main to side to condimento.
Kick off your line with the foundational starch—polenta, rice, potatoes, grain salad, etc.—if you have one. That goes down first.
Next comes the saucy part, maybe the meat or fish, or the saucy bean or vegetable dish, the thing you want to go on top of or nestle up to the starch. (And if you have a separate sauce for the main dish, make sure to set it super close to its intended. Get them so close they touch. You have to make these pairings obvious in a buffet.)
Like in flower arranging, you want to emphasize these main showy dishes by leaving some space around them—in this case, so the buffet-wender can set down their plate if necessary. The rest of the food can stretch out leisurely the length of the table.
I find that platters rather than bowls are key. No one wants to have to peer in to see what they're eating, and besides, everything looks better in a shallow vessel. Take a roast chicken, for example. You think you want to serve it in a high-sided roaster? Nah, it looks so much better when you carve it, splay the drummies, slice the breast meat, pour the cooking juices over the meat and tuck lemon wedges into the empty spaces. Which leads me to:
The only things that need narrower bowls are those that need to remain hot; rice, for instance, which I like to serve in a deep, thick-walled clay bowl. Though if you're worried about keeping something hot, you can also warm the platter briefly in a low oven.
Spreading the food among platters also shows off their garnishes. Gewgaws and bling are life's essential candy. Whether these enticements show up on a party platter or on a suburban wall, they matter more than you think they do, probably more than they should. Anyway, except for tufts of herbs and candy apples (unless your menu leans retro) decorate every dish with a tiny garnish that improves it and can be eaten. For example, strew some crispy fried shallots on your pork; balance a mound of lightly crystallized pepitas on the turnip salad; shower the grilled vegetables with some fresh pepper; stop the top of the bottle of hazelnut oil with your thumb and shake it until a few fat raindrops of amber oil falls on the polenta, and so on.
In other words: goose it up. Everything at this party is on display.