Post number nine pretty much covered things, but it's hard for me to relate to the OP's problem with friction shifting because I don't recall having any issues at all with the friction-shift Campagnolo Super Record drivetrain on my first road bike. I'd just reach down and give the lever a little flick one way or the other and it would "snick-snick" right in to gear, without a lot of futzing around with trimming after the shift. Most often, it'd go into the desired gear combination with no trimming required, and no major brainpower on my part to make clean shifts happen. They just happened. Way back when, index shifting seemed to be a solution to a non- problem to me, and I kept running my old Super Record stuff many years after the industry had switched to index shifting exclusively. I seriously don't think I'd miss the click-shifting Shimano 105 of my current mount if I hopped on a vintage road bike with old-school Super Record tomorrow. I'd just hop on and enjoy the ride. I still LIKE downtube shifters and while I've ridden bikes with modern "brifters" or shifting integrated into the brake lever, I've never owned the setup and have no burning desire to do so.
J.