Any thoughts on stats? I would probably make Boxers themselves tribal. There is a case to upgrade them to represent their fanatacism but as one of their key strengths was thier numbers I am loath to reduce this effect. Any Imperial troops might best be represented as Irregulars to emphasise the difference in quality compared to their opponents.
What about the Allied contingents? All simple regulars or should anty nationalities be upgraded or downgraded?