I commute two days a week on a 1962 Raleigh Superbe. The frame may be a later model, maybe 1970.
I laced a new 700 c rim to the old SA 3 speed hub, out drop bars on it, put a set of Modolo brake levers and calipers on, and modern pedals.
It also sports a rear rack with a child seat so my son Henry can ride home each Monday and Tuesday through downtown Seattle from his pre-school. The weight of the bike with him on, not counting me, must be fifty or sixty pounds. He weighs 28. At least that's how it feels going up the West Seattle hill in the evening. And that's after eliminating the weight of the chain cover, the steel Raleigh rims, etc., etc. Did I ruin a sort of classic? Maybe, but it's a runner!
The other three commuting days are on a Fuji from the early 80s converted to fixed gear.