CloudRedirect can now backup your luas, achievements, your playtime. If you login to a new PC, your luas automatically sync. Restart Steam, the luas/achievements/playtime are there. Magic. This is off by default, enable it in Settings.
Achievement sync merges your achievements between machines! If you've been playing the same game on two PCs and have different achievement progress on each, it'll merge them on the next launch, keeping the higher value. Playtime sync does the same thing for playtime in localconfig.vdf. Takes the higher value from either side. Both are off by default.
Setup also got some quality of life work. There's a DLL repair option now if your core DLLs go missing or get corrupted. And the initial Steam bootstrap after patching is handled automatically instead of just telling you to restart Steam.