The only orks that really develop unique personalities are warbosses, from Ghazgkhull taking a bolt round to the head and becoming Prophet of da Waagh, to Nazdreg who was a good tactician and spoke fluent gothic, to Snagrod who liked to set entire worlds on fire for shits and giggles.

We can't all be warbosses though, unless we were lesser bosses all part of the same massive Waagh. I'm not sure how that would work though, and that's sorta entering the realm of a nation rp if we all had our own armies.

Other than that, there's always the oddboyz.