Welcome aboard!
I'll agree that the 'front end' of the game looks a little dated compared to more modern attempts, it's all done in 2d using icons etc, rather than more modern Rendered interfaces. Parts of that is changing slowly, such as using a proper model of the ship in the Loadout screen etc, but much of it is simply down to the way the game is written, it would be nice to have the ability to feel more a 'part' of the crew during a campaign (Freespace 1 did this to a small degree using cutscenes) but it's a huge job, and not one I really see taking precedence at this time.
As for short missions, I noticed that too, it's partly because, in the original FS2, you cannot get your hull repaired in-mission, so your surviveability drops quite a lot compared to games in which you can. The missions do get longer and more drawn out nearer the end of the campaign, but not exceptionally so. That will probably change in Mods with the new features of the SCP.