I know the feeling! It bugs me when the whole car is not 100%, but that just isn't possible on a 10 year old car without rolling your sleeves up and opening the wallet!
Did you torque the 21mm top nut down, or just air gun it? There is a risk of over tightening that nut, which can prematurely wear out the ball bearings. If the wheel has no vertical play in it, it's not the bearings.
Another source of knock can be the steering rack. The actual mechanical rack/pinion part, not the electric motor side of it. How many miles on the car? Mine's on 110K and making all manner of clonks, clunks, clicks, clacks, crunches, knocks, bangs and thumps! I did the top mounts/springs/dampers last month, so I know it's not them!