Get down to machine mart and pick up a long flex head ratchet to go with that lot. I'm a late convert to the flex heads, but they definitely have their moments, plus the extra leverage is handy. They're only £20 or so, reasonably robust.
I say 1/4", 3/8", and 1/2" is needed, that is if you just work on cars and light trucks.
You can probably get away with 1/2" but plan on breaking ratchets/sockets.
