Older Campagnolo ergos are actually not that
difficile to set up and quite forgiving. 8 speed Ergos will also work with 7 speed freewheels no problem, in case you want to continue using threaded hubs.
Derailleur I think are (correct me if I'm wrong) usable for 8/9/10 speed, as are most rotors from ~1998 on.
Is 10 speed worth it? Absolutely, I run a record 10 speed system on my
#1 riding bike and love the intervals I use 50/34 and 12-27. Never felt the urge to upgrade it. It worked flawlessly with a number of different cranksets and chain wheels including some originally 8 speed stuff (PCB road cranks, 1st Gen SRM...) currently I run a 2017ish Athena (11spd) with a KMC chain.
Mind you things may be different if you like to use (much) larger stuff on the rear.