I would summarize the differences as follows:
The 200 weighs approximately 256 to 258 lbs dry. I believe that means there is no oil in the engine, no fuel in the tank and helium in the tires.
The 350 weighs about 295 lbs using the notoriously optimistic Japanese scales from the mid-eighties. My lower back pegs the number closer to 325# when I try to lift the Great White onto a stand.
The wheel base is very slightly shorter on the 200, which would impart a slight agility advantage in technical conditions when coupled with the weight disparity.
The 200s were produced in greater numbers thanks to their longer production run. However, the 350 has the MonoCross(tm) rear suspension which is easier to find a better shock for.
Some of the 200s were kickstart only. Others had electric and a kick. All of the 350s had electric and kick start, except for Cliff's #2 bike which has been enlisted in the Hollywood Madison Maintenance Program.
The biggest difference is, of course, that giant, steam-breathing, muscular mass of an engine on the 350. There simply is no more manly BigWheel than the mighty 350 Electric.
That being said: when Cliff and I were returning from the ride on the B-29 Trail we were riding on the shoulder of the road and passed a female rider on a TW200. I waved, expecting some recognition of kinship between the BW clan and the TW clan.
We were snubbed.
The conclusion that we reach over and over is: regardless of displacement, BWs are repulsive to the fairer sex.
Really? How could you possibly snub Evel Kliffneivel when he looks like this: