For my money, I prefer to continue to think of the UFP in the more traditional "utopian idealism" mold that's been part of Trek from the beginning.
^^^
You really need to watch more TOS as the '"utopian idealism" mold' you describe WASN'T a part of Star Trek (which began with TOS 1966-69) from the beginning. Yes, TOS had better people who had overcome racism of Earth (but still held it towards a variety of aliens.) people still WORKED for a living and earned money (Federation Credits). If the time of TOS WAS a Utopia and the Federation a moneyless society, Harry Mudd transporting wives for settlers or getting caught selling rights to a Vulcan fuel synthesizer to the Denebians - (rights he diodn't own, and thus was sentenced to be executed for fraud as the Death Penalty seemed alive and well of Deneb V. (see TOS - "I Mudd") or Cyrano Jones making a living prospecting and selling trinkets and Tribbles wouldn't exist.
Hell, as show above, in the TOS era, the Federation let member worlds KEEP their own laws and racial/social traditions, no matter what they were - and respected a Member Planet's local laws EVEN IF they didn't align with Earth's societal norms.
^^^
It was TNG in 1987 that started to retcon all the above stating:
- Earth was now a Utopia and everyone worked to better themselves because all basic needs were provided for and money was no longer used.
- To be considered for and ultimately attain Federation Membership, a world had to agree to abide by Federation (read: Utopian Earth as the basis) to 'Federation societal norms'. (And hell, the enlightened Picard chewed out Worf on multiple occasions because he dared to do something 100% ACCEPTED (and often encouraged) in Klingon society - but because they were agaisnt Picard's Federration beliefs Work got many a formal reprimand on his service record.
So yeah, the 'Utopian' bit was a TNG era retcon; and not a part of 'Star Trek' from the start AT ALL. (And IMO 'Star Trek' is better off WITHOUT that TNG retcon.) YMMV.
