For sure out of BK you can't beat Victor1 and harbour orbits for pleasing pax. Plenty of CPL's out of BK built all their command doing a thousand of the things (not recommended!).
Definitely Katoomba to mix it up a little, and over the range (esp early morning or evening - the light on the ranges is incredible).
My personal pick for a day trip though would be Merimbula, has to be one of the nicest aerodromes on the east coast. Bit of a trip down in a warrior or the like (2-3hrs each way) but short walk into town to enjoy some fresh oysters and a lazy lunch by the harbour. Really great place and you'll get a few hours under your belt, some CTA work through Nowra if you want it and maybe even a CTA arrival via picnic point into BK too on the way home so you can take something out of the flight too. Worth stopping at Moruya and even the gong too for a coffee if you're up to it (and if time permits!).