Pecs is small enough that the only real decision is how far up the Mecsek you sleep, and how much Friday-night terrace noise you are prepared to take.
Belvaros — inside the old walls
Szechenyi ter, Kiraly utca and Ferencesek utcaja, with every major sight inside a ten-minute walk. The trade-off is Kiraly utca itself, which runs loud until two or three at weekends and is where most of the cheap central rooms are.
Zsolnay Quarter and the eastern edge
Around the old porcelain works, roughly twenty minutes on foot east of Szechenyi ter. Quieter and sensible if you are here for the museums and the Kodaly Centre, but you walk back into town for a late dinner.
Uranvaros and the university side
West of the centre around Ifjusag utja, where the university and its 50-metre pool sit. Apartments and guesthouses are cheaper here and it is a flat fifteen to twenty minutes into the old town.
Up on the Mecsek at Arpadteto
Forest above the city, several degrees cooler in a Pecs August, with the ridge trails and the adventure park on the doorstep. You are dependent on the bus or a car, and nothing up here stays open late.