I have an older Dr Dew - triple crank, hydraulic discs, etc which mainly sees the MYT from out Warrandyte way into the CBD. It's also done a nubmer of rail trails.
At the outset I replaced the saddle.
I've put a rack, mudguards, lights and SPD pedals on it. And I put some bar extenders on for alternative hand positions, although I don't use them that often now.
Drive train and tyres replaced due to wear. Tyres went from the original 35s to 32s - my bum is a bit tougher now.
If I was starting again with the experience I have now I would also consider a CX bike, but I have no reason to replace the Dr Dew.