When to go
Spring and autumn give the broadest fit for the city, Hills, coast, and wine regions. February and March can be exceptional when the festival calendar is the reason for the trip, but event tickets, restaurant tables, hotel rates, and street closures all need earlier decisions. Summer heat and fire conditions require flexible touring, while winter suits interiors and a slower Hills stay.
Hotel logic
The base should solve the trip. Eos is the contemporary Festival Plaza choice. Sofitel, Mayfair, InterContinental, The Playford, and Oval Hotel each create a different city geography and atmosphere. Hotel Indigo makes sense for a market-led stay, while Sequoia Lodge and Mount Lofty House turn the Adelaide Hills into a retreat rather than a nightly commute. I would confirm the exact room, view, event noise, works, and transfers before treating any of them as interchangeable.
Food and reservations
Restaurant Botanic can anchor the destination tasting, Africola brings fire and energy, Osteria Oggi handles pasta, Arkhé works around wood fire, and Parwana tells a specific Afghan family story through dishes such as its eggplant. Fino Vino and Herringbone bring a warmer ingredient-led rhythm. Central Market should be a guided grazing morning, not a rushed stop between attractions, and its Tuesday through Saturday pattern needs to shape the itinerary.
What I would avoid
I would not stack Barossa, McLaren Vale, and the Adelaide Hills into a race, use Glenelg as the automatic base, or attempt Kangaroo Island as a day trip. Hahndorf works better as a short history and producer chapter than a theme-only bus loop. During Mad March, improvising the important hotel, restaurant, and ticket decisions is the fastest way to spend the premium without getting the festival trip you wanted.