I understand why people might not like random chargen, but examples like the OP gave of wanting to be a Marine and ending up a hobo aren't my experience with how it actually works in practice. It is theoretically possible. But its super unlikely.Exactly. My female Aslan character has no Events, no Mishaps, none of the Advance rolls to show her climb to the top (or the failures that caused her to switch careers), none of the I-wanted-Astrogation-but-got-Diplomat rolls that turn out to be fortuitous, none of the Mustering Out rolls that add the finishing touches and possibly grant me a ship. I had to pay points to get my money. I had to buy my rank, which was basically meaningless, except as window dressing.
Random chargen is a game within the game that makes it more enjoyable. Having the built-in aspects of Traveller character building is an essential part of the game in my book.
In my current campaign, of the six players... 3 got pretty much what they were aiming for, two got basically what they wanted but via a roundabout path, and one got totally derailed by rolling a psionics testing event in college and choosing to run with it. Once you factor in the connections rule and the campaign skill pack rule, it's quite hard to get a character that doesn't do the kind of thing that you want your character to do, no matter how the career rolls go.
Obviously, if you have a very specific concept (Former Navy Commander ace fighter pilot), that's not likely to be how your character turns out exactly. But if you are a little less specific "I wanna be a hotshot small craft pilot", it's going to be pretty hard not to get that out of chargen.
TravCompanion chargen is functional. But if you want a strong link between the basic game mechanics and the various externalities of chargen, you need to use a dedicated point buy system like the GURPS or HERO versions of Traveller.