Character development in Traveller has never really existed. You play, and the playing is the thing to enjoy. You might develop contacts and resources, but you equally might not – character development simply isn't the point of playing. Your character is your means of exploring (or exploiting) the universe.
A character that is numerically static is alien to the sensibilities of gamers brought up on most current RPGs, but some games simply don't have the character-advancement subgame and that's not a flaw. An assumption that development must be somewhere in the game will lead you astray looking for it, so try to let it go and understand the game on its own terms.