Character generation, ship building and world generation are games within themselves, as well as being tools with which to construct the game universe.
The thing I always disliked about D&D was the "here's a dungeon, there's gold, kill the monsters to get to it" game. Maybe it was the D&D DMs I played under, but Traveller appealed to me because it offered more than that.
Some people like the Trader game - buying and selling cargo, making the books balance, paying the starship mortgage - accountancy in spaaaacccee! - and adventuring (with shooting) along the way.
Others like the Traveller game - hiking round space, getting into scrapes and adventures, shooting things/people, and so on.
Then there's the Mercenary game - gun pr0n, dropships, sentry guns, grav tanks (or tracked tanks), achieving a military objective (or not), blowing stuff (and people) up, getting paid and moving on to the next ticket.
The Diplomatic game involves intrigue, deception, lies/deceit, manipulation, double crosses, double-double crosses, wealth, mingling with diplomats and nobles, usually with the aim of pulling a fast one on the opposing side, or gaining the edge in some manner - such as a lucrative trade or arms deal, bringing a rogue noble to heel, or somesuch.
The Navy game is a starship variant of the Mercenary game, involving space battles, boarding actions, invasions (sometimes), ortillery, and blowing (big) things up. And shooting.
The main thing is to make sure that NPCs have character and aren't all human. A Hiver diplomat trying to talk down a Vargr ambassador after the Vargr has had a few drinks at a post-war peace reception is a tricky situation, and can lead to all sorts of problems for the PCs.....
These are just a few of the possible game "types" for Traveller, but are the most common ones I've played or Refereed (others MMV). When it comes to things like plotting Jumps, docking starships, setting up an artillery piece whilst under fire, calculating a geostationary orbit, etc., the character's skills and attribute DMs come into play, along with any other DMs the Referee might throw in for good measure. The ref sets the task difficulty, the player throws 2d6 and adds the DMs, and you get a result (good or bad). You don't actually have to know how to calculate an orbit as a player (although sometimes it does help) and the Ref should be able to tell the players about the gravity on Zircon IV - "it's 0.6 G, so you can jump a bit higher, but coming down is tricky".
Here's an example from a game I played in - oooh -1980-lie:
My character and three others were walking across the underside of an Imperial Navy battleship in orbit (we had Vacc Suits on, obviously). Our goal was to plant a bomb on the communications relay, get out and blow it (before we were spotted). This would prevent the Imperials calling for reinforcements prior to our Solomani battleship arriving and destroying the Imperial ship. So, we made our way across the hull (magnetic soles, see?) and found the spot we were looking for. The bomb was planted without any problem and we all thought "job done, home and tea!".
Except for the fact that placing the bomb on the communications relay caused interference, which the Imperials then checked out and we got spotted. Marines were despatched out of an airlock in front of us some 20 meters away, so we turned back towards the relay and tried to run for it.
Whilst wearing Vacc Suits.
With magnetic soles.
In zero-G.
The character with the bomb trigger tripped and he failed his saving throw. He landed face down (up?) on top of the bomb trigger and set off the bomb. Our characters died from the blast.
The End.
In all of the above, we didn't need to calculate anything - the bomb's blast radius was 50 meters, we had moved 20 meters away from it when we were spotted and decided to turn back. The Ref had determined that wwe had to move at half normal speed due to the Vacc Suits and magnetic soles - about 1 meter every 2 seconds. Boom. Shredded Vacc Suits all round, barman, and a chaser of a hole in the Imperial ship's hull.
