I'm guessing I'm a decade or so from needing considering a mxite, but, reading the posts and looking at the photos --

So, Shifter locations: I see downtube shifters, stem shifters, bar-end and I guess thumb shifters would be fine with upright bars. Has there ever been "downtube" shifters somehow mounted on the, hmm, "upper downtubes", the twin ones? I guess either a very specialized clamp-on, or have bosses brazed on. And the routing for the RD would be straightforward enough, but the FD... one of those with the cable entry from the top? And would the results be a natural hand drop from the bars to reach the shifters there? It seems possibly better, no interference, than the traditional downtube mount.