The "Swiss Edition" is available (respectively, was - lately only 3 or 4 are left unsold at the dealers) only in steel.
Iīm not aware of such a piece or something likely to come in the future.
Still you may find the 2006 cases interesting; the weight is less than earlier pieces, without loosing the substantial feel all WW.TC do have.
I find them more comfortable, even for my small wrist.
In terms of Titanium, iīd recommend to have a closer look at the "Berlin" edition.
Thereīs a couple of impressions in earlier posts; itīs not only rare (49 pieces, available in Germany only), but i find the colours to be subtle either and not as colourful as other TI variants.
But the best thing is the polished TI case; a wonderful smooth feeling when you touch it and a very special shine. It really makes a difference.