That is the question, I think enough of it is skill based that you can and do improve with every run. If it was completely luck based it may as well be a slot machine, but just like with Isaac (I know, I bring it up a lot when talking about FTL) the luck based item/resource finds make for what can be a more enjoyable experience because it's not always going to be a series of the same moves made to accomplish the same goals.
I normally try to have someone manning the Weapons, Engine, and Piloting at the start, but depending on what the first jump beings I'll have to use the skills gained from previous games to make the right decision going forward. That single decision could lead me to my ruin 5 sectors from now. More so than most games, your decision have influence on how long you're going to last.
Of course, just like with any 'roguelike' you're going to get screwed by the RNG every so often and just run out of fuel within a few sectors. But that luck based event will affect how you play going forward.