Poll posted. Partly agree with you, but unification itself may not mean THAT much. Just look at China under Mao
Unified, but even worse than in the warlord years.
Even with a Mao-like dictator in power, being unified
may be better than being disunified from a strictly utilitarian point of view--much depends on whether this hypothetical dictator can avoid the Second Sino-Japanese War and what his exact policies are within China itself.
In any case, I voted for "Yuan Shikai doesn't lose his nerve in 1898". Besides earlier PoDs usually being "better" (more powerful, because of effect propagation), this seems like it would both allow a relatively united China
and hopefully avoid the dictator issue you bring up. I somewhat doubt that the late Qing emperors were, even without certain toxic influences, powerful enough to impose a modern-style dictatorship (or, for that matter, willing to), but they would likely represent a power base large enough to prevent other elements of government (the Army, a Prime Minister analogue) from doing so.
Ideally, of course, Yuan would bite a bullet while fighting down Cixi's coup. Take out two birds with one stone