If it was an old house, I'd rather change the wire and keep the nice
old fittings, but I guess that's not advisable,

You're right. The problem with old fittings is that the insulation in them
will normally have broken down by now and be unsafe, just like the the
rubber insulated cable originally used to connect them. I intend to get some
reproduction ones for my house with modern internals. In particular, some
round Bakelite light switches for the hallways and a couple of dome brass
ones for the principal rooms.

Christian.