1) No, the ballista range is not biased information. It's the AVERAGE range of both. And both had "DIFFERENT" ballistas.
2) Seriously, what do you expect Chinese "fanboys" do? It's a ROME V HAN discussion. The point is you take a side, and talk about how "great" their army is. Not to mention that I've seen more than a few posts that says they don't know anything about Han military, and still say that the romans would win, so I doubt you can call the Chinese histoy forum biased, who actually knows something about roman military<no offense>.
3) Rome lasted more than a thousand yrs if you count the Roman Republic, and the Byzantine Empire, not to mention the NUMMEROUS number of successions that took place. The Han lasted 400 with ONE succession<after the succession it moves to another dynasty, not a whole new empire>. You want to count the whole Chinese empire, like the whole Roman empire, than it's +3000 yrs.
4) Just because a country is ahead of another doesn't mean they can counquer the known world. Rome didn't do it, but people here don't ask why "if their ahead why didn't Rome conquer the known world".
5) As i have stated, Rome's formations against arrow fire is INEFFECTIVE against Han arrows. They are only effective against Roman ones. You can't just reject it without proof. Remember carrhae, their formations was quiet useless against Parthian bows, which is also behind that of a recurve bow. Yes the Romans had ranged weapons. That doesn't mean they have the best. This is the reason why the Han didn't have hulking shields against arrow fire, not shields made out of plywood, as well as looser formations against it, instead of mass shields, which would basically mean asking for death.
6) Both sides have tactics! I don't know why people can't figure this out. It's who's in command that's important. Of course both sides have good generals, but both has bad ones as well. It just depends on who is leading the army, a good general, or a lazy drunk?
7) Do you really think Han armies don't have volunteers as well?
8) Everyone's "built" to kick the other sides butt, this is an obvious.