PSA: historians tend to side with empires because empires leave things that historians can study, like texts and stone monuments and whatnot. free peoples are much more likely to rely on organic materials and oral literature, so they end up without a presence in history. (as someone said, history isn't written by the victors, history is written by the writers.)
so you have to look at archaeology, and when you do that you find that life in the "dark ages" following a "collapse" of an empire—Rome, Maya, Han etc.—was actually better for the commoner than during the high imperial times (skeletons show signs of better nutrition, less disparity between people, better health markers etc.). Empires are good at creating great monuments and whatnot but if you're ever killed by truck-kun and reborn in premodern times, aim for the distributed confederacies of a "dark age" rather than empires at their peak, because in a stratified society statistically you'll be a slave or servant of some kind and it's much less fun. (early medieval peasants not only had better nutrition than their predecessors but also than early modern urbanites, a gap only closed in the 20th century.)
the same goes for stateless people, often called "hunter-gatherers" even though they usually know about agriculture and just choose not to rely exclusively on it:
> The lives of those within these fluid civilisations were not poor, unhealthy, or doomed to be 'short and nasty'. Ice-age foragers were taller and in better health than the farmers who took over the world. Today, foragers are less likely to face famine than non-industrial farmers. The modern forager-horticulturalist Tsimané of the Bolivian Amazon have the lowest rate of atherosclerosis of any recorded group. They also experience less brain atrophy than their industrial counterparts, losing 70% less brain volume as they age as their peers in Europe and the USA. The Tsimané are not an outlier. Reviews of hunter-gatherer populations have found that they have exceptional health; findings even more impressive given that modern foragers are often marginalised groups. (Goliath's Curse)
life in indigenous societies is so much more attractive that the early colonists in the USA had to put armed guards to stop white people by force from just running away from the Euro lifestyle to join confederacies , with Benjamin Franklin lamenting that if a civilised man tastes of the "savage" lifestyle they never go back, while every "savage" refuses civilised life unless forced to it. the main criticism the USA colonials could make about indigenous societies is that they were *too free*. when being reborn in the past, try to hit one of the peoples who didn't write much, like the various folk of Turtle Island or Atearoa etc., and you'll be much better off. if you fancy a more urban lifestyle, try one of the "dark ages" megacities (teotihuacan, nebelivka, çatalhöyük etc.).