Rootboy already mentioned some of the more blatant items that can be improved upon: brake cable length, toe strap threading (although I disagree about double twisting, one 360° turn is always sufficient) and addition of the lever hoods. You might also want to switch the routing of the rear brake cable to the other side of the seatpost (it is more customary to have it run on the non-chain side to prevent it getting in the way of adjustments of the seatlug bolt), lower the stem somewhat (This is for safety! These old Cinelli steel stems do not like to be fitted that high, I have seen some get creased when raised that high especially when they are as long as the one on your bike), lower the cable guide at the BB so that the rear derailleur cable is perfectly parallel to the chainstay (your appears to be higher at the front), plus the replacement of the missing ring from the rear Q/R skewer.

With the bike as beautiful as it is already, it can only get better!

Right you are Citoyen du Monde. One twist of the toe strap inside the pedal cage.