OK - here are the scales I like for Gladiators ....
This posting is partly to show I read the comments you send ... partly to illustrate why I'm not bothered with 28mm ... and partly just because I like gladiator figures (hey ... it's the Society of Ancients - it's allowed)...
Actually, if the brilliant Revell 90mm plastics had been available all along (and if there were more than just these two, of course) ... I think there's no doubt this would be the winning general purpose scale.. they are chunkily impressive, obviously robust, and retail for under a fiver! Come on Revell - make a few more variants!
No - they're not real people, they are toys!
Even so, the little guys still have a charm all of their own - so if you go properly big for a combat game, there's still scope for a Slave Revolt army (and no real need to be too scrupulously 'purist' ... mixing a few gladiators into the ranks tells you something about the characters, even if they are no more likely to have fought in 'costume' than Napoleon's guardsmen!...)
... and so, just for fun ... here are some of those 15s again: