Tyga is a member of YMCMB records and is only 22 years old. He's been featured and made his own music tracks with currently some big names in the music industry such as Lil Wayne (Tunechi), Drake, Nicki Minaj, Chris Brown, The Game, Wiz Khalifa and so much more.
Rick Ross is the founder and owner of MMG and is currently 36 years old. He's participated in huge music tracks, owns his own music group and has been created some great music. He's got a unique style to others and he's created music tracks with Drake, Lil Wayne (Tunechi), DJ Khaled, Wale, Meek Mill and many other artists.
They personally don't have anything in comparison as they've got two different styles. Tyga's more into the woman side of things and Rick Ross is about his money. Which artist isn't about money and woman, though? They're both good in their own way and arguably can be said either one's better but that's just down to personal taste. I listen to both of their music and I am fans of them both - that's just me, though. I personally can't answer which artist is better as it's too close to decide as they both produce good music.