The WG if the watch is going to be used primarily as a dress or special occasion piece. The Ti if it is going to be worn more often and regularly -- I fear that the rather wide bezel in WG will scratch easily if worn less than very carefully. This is probably my favorite modern Cartier.
In the end, I think I would opt for the WG, as the ADLC may be a bit too trendy for such a fine non-sports watch as this, and I think this is a watch one would want to keep for a long, long time and survive fashion trends.
Best,
respo