I suppose I could argue further as to how such terms as "libertarian" and "utopia" are meaningless in the context of LOTR in general, and The Mark specifically.
However, how we discuss the upcoming scenario and how it actually gets written will most likely be two entirely different things, and if we are (more or less) true to the spirit of The Mark of the early 4th age, with rogue lords (which in the case of 4th age Mark would merely mean richer and more power landholders than those around them), then everything will be fine.
Speaking of which: the way it would really work in The Mark, economically, early 4th age, would be thus: The strata of government consist of king, eorls, and land holders. That's it. There is one king, now three eorls, and many landholders. Some landholders are more powerful and richer than others, and it would make sense that war veterans (if they took loot home especially), would be richer than most.
If these richer landholders are wily, they could perhaps (if they really put their minds to it) devise a plan that over the course of 14 years results in an additional layer of stratification because they were able to put a lot of other landholders around them in their debt, thus causing themselves to be seen as lords, especially seeing as this particular piece of The Mark seemed to get lost in the shuffle - which is why Eomer created the Middle Emnet Eorl in the first place. Would that work?