The ceramic rads are all great, from the 292 to the 384 to the 643. I personally would go for the 643, as it offers a pure base dial with the interest of the waffle dial, which I find contrasts really nicely with the brushed black ceramic.
Or, the 292 for even more simplicity, if the 643 doesn't do it for you.
As for the 384, I think the "fang" power reserve works much better on a Luminor like the 233. Rads really are most special, IMHO, with two hands and 3/6/9/12 on the dial (or the Cali dial, of course). YMMV.
Good luck with the choice!
