When I first saw Paragon I didn't know what I had done to deserve such an awesome and esteemed title - by definition most perfect example of skill and contribution, a model of excellence. Exceptional.

Yay new titles though!

Much like you I only spent a few hours in BGs and got those three titles.

Battleground butcher - win with 500 before any other team gets 200,
relic-runner,
paragon - your kill ratio must be 8 times higher than your death, i think? its a k/d ratio one. currently moderately hard for some classes, easy for others. bow/mag sorc builds get this easily by killing blowing with ranged, whereas people like me had to work hard as im a medium wearing yolo 4.2k weapon dmg boss hog that has to get in the thick of it to get killing blows.
bloodletter - 1000 kills - assists count,
grand champion 50k points over time? soemthing like that,

they are all easy/rewarded with time. BG Butch comes from the borked queueing of 4v2v2 - currently easily obtainable

they are in the achievements list