My TU isn't "setting free". It has a setting, but of my own conglomeration -- not from the canon.
I am an infidel in that I do not worship at the temple of OTU, that rigid and jealous god of Traveller gaming.
IMTU:
My campaign is 95% based on the wonderful "Dumarest Saga" novels of E. C. Tubb, 1% on
The Mote in God's Eye, 4% other (inspired by 40-some years of scifi readings far, far too numerous to mention by name or author), with campy-fun goodness sprinkled in
ad gustum from
Buck Rogers in the 25th Century and
Battlestar Galactica to lighten things up. There is a corner of my Traveller universe where I have my own version of Barsoom, but I choose to use OD&D (+
The Warriors of Mars wargaming book publ. by TSR in 1974).
Nobility? Yup, I've got 'em, also derived mostly from Dumarest, with a little of the Niven/Pournelle novel, too.
I don't use the official milieu (aka travellermap.com)...which is a very immersive, entertaining website getting those creative juices flowing, but I have my own sectors, realms, empires, etc. I favour a nearly-pangalactic scope, compared to the disappointingly small flyspeck of the Imperium and contiguous domains.
In relation to the previous, my tech has kiloparsec drives. These are restricted tech only available to megacorps, militaries, govts, a few very powerful noble families (who themselves may control shipping in their part of space), while the bulk of civilisation must make due with the J1 - J6 drives seen in the RAW/BtB. When I saw David Lynch's DUNE for the first time and witnessed the grotesque wonder of the Navigators, I've been dying to include some concept of that IMTU, but have thus far resisted.
I discard the canon races, save the Hivers...because they are very alien and cool

My aliens are weird, funky, non-anthropomorphic: amoeboid Dralasites (from TSR's Star Frontiers RPG -- minus their love of humour and jokes), hive entities like swarms of polychromatic fireflies, ichthyoid species, mineral species, the Silkie (from the A. E. Van Vogt novel of the same name), plus some mutants from nuked planets. Lizardmen (like the Sleestaks of "Land of the Lost"), and man-sized frogpeople are also part of the campaign! No kitty-cat (Aslan) nor puppydog (Vargr) aliens, if you please!
I intermittently use the RAW chargen, but frequently just like a freeform chargen (pick a class/career; pick skills, the points of which are the sum of INT and EDU; add a little backstory and a few flavour bits; equipment; credits; weapons...and SHAZAM! All done!)
If I were to include a concept of "Ancients" they would be inspired by the Krell of the movie
Forbidden Planet: extinct, mysterious, and having left far-flung colonies of ruins and a few rare, incomprehensible artefacts.
I find the OTU ships serviceable, but 'basic', in the current parlance.
A final note: MTU is definitely NOT at all based on that quaint, small-budget movie by Gene Lucas!

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