The only reason this game is not a wold wide hit (just a niche game for the simulatorly retarded) is the controls system. I don't say X3 is unplayable, it's quite handy when you get the hang of it, but it does have a steep learning curve...that is almost a brick wall...
For easy access you would need two keyboards, a joystick and a mouse...all at once. The controls and the menu system is horribly unintuitive and hard to navigate...again, for the novice players. I had no trouble with the controls...with almost 50 hours of playtime under my belt that is. It's a very lengthy thing to learn the controls of your own ship, let alone the automation and the rest. If you waded through the tedious session of learning the keyboard layout, the menus and the systems, so when you are controlling a big fleet of ships and you meet an enemy fleet, it's almost second nature to hammer in orders for strategy, attack and formation for the entire fleet while driving your ship, all the while giving orders to the transports two galaxies away and managing your factories and... well, you get the picture...
And you do need to do all these things because simply you can't succeed with one ship only. It would be awesome to be able to upgrade a given ship to meet your needs, but upgrades go only so far in X3. Of course you can buy bigger, more advanced warships, frigates, battlecruisers and the like, but even with a battlecruiser, without fighters and support you are simply dead in the water (space) against a balanced fleet.
What the X series needs: an intuitive and handy interface, where you can find anything you want with a few clicks, not digging to the bottom of layers upon layers upon layers of menus to find a single command. A good upgrade system, where you can upgrade your ships to meet your needs, so you can be (even partially) successful with even one. Better factory management. No more unfair gameplay, unfair missions and insurmountable odds. And the last one is: an interesting story (however remotely).
IMHO.