First off, buy what you want to play.
Second off...it's too early to say what a lot of us will want to play....
RIght now, there isn't much beyond combat. Yeah, a few PI missions, etc, but almost everything revolves around combat of some sort or another....either doing it, or avoiding it.
Once 3.0+ hits, we should start seeing some of the non-combat roles. That will really be where we see how much depth this game will have. It's here where we will lean just how viable cargo running, mining, exploring, etc will be.
Oh, and for all those people saying how they will hire NPCs to pilot fighters, etc...as far as I know, the only thing that has been said is the ability to hire NPCs for multi crew ships. I have not seen anything official about being able to hire an NPC to fly your fleet of fighters as escort while you pilot your Hull-E. Now, that said...they may put that mechanic in, or they may not. Even if they said they would be doing it, we don't know how good they will be.
My advice (which I admit, I did not follow myself), is to wait and see how 3.0-4.0 progresses and make your ship purchasing decisions then, not now when there are still so many unknowns.
Finally, there are a lot of us with extra ships...we can't fly them all at the same time... come crew with us or maybe help escort us....if I need a fighter escort, I would rather get a real person over an NPC, even if I have to loan them a ship to do so.