There is still time to change the menu. If you would rather not do a 'crockpot' brunch though fast and frugal, but would like something with a bit more elegance and still be fast and frugal then try this. Though changing the hot menu on the host's part, you 'the host' can still ask guests to bring a salad/fruit/cheese or desert tray.
As this is a brunch, it is wise to have guests bring dishes that don't require heating or being kept warm. You as the host however, should provide dishes that are served hot/warm and even if they cool, will still be incredibly delicious. Now, if you go with the earlier suggested crockpot dishes, its a no brainer... they will still warm keeping that setting all the while you eat. And, its nice to have them on a buffet table plugged in against the wall. This way, you the host can enjoy eating and visiting.
However, I did promise to tell what to do if you want something different... not crockpot dishes. So, in that case, I highly recommend cooking one kind of lean meat which could be either beef or pork cutlets. Use small thin steaks or medallions sauteed in olive oil with seasonings. These would be prepared as guests line up for salads, fruits and cheeses. The meat in this size will cook quickly. Once done, set aside on a serving platter and cover. Then in the same skillet, saute fresh asparagus. When the edges blacken, turn out onto the same platter with the meat and in the same skillet do a cheese omelette topped with diced tomatoes or even homemade jelly. Guests can come to you at the stove/range on counter or you can set out the hot food as they begin to make their way to the main table after they have visited the salad/fruit/cheese buffet.