Gotta get away from the drops -- I'm in my 70s and the drops are just too hard on my arms. Also, trying to look up while on drops gave me a continuous kink in the neck.
Did a 1200 km tour last summer on bullhorns and found the same issue -- my arms and shoulders ached for the first 600 km.
A 4-day tour on my old Pugeot with riser bars was comfortable with no issues (except that the higher gearing made the hills tough). I'm not in any hurry and don't need the aerodynamics of a dropped position; I also prefer having my head up to look at the passing scenery instead of head down looking at the road. When your body is comfortable and you're not leaning forward, you don't NEED multiple hand positions.
Going to try trek bars (figure 8) this summer.