Anyone have one big cool mod that covers everything? Like totally change the whole system to work better and have a lot more features?

Most of the mods do just that.

Any recommendations? I have a X910bt. I can only find Navigation mods, for the F Series, and other things that seem kinda iffy(with a lot of bugs not worked out yet) to install. Do mods for F-Series work on X-Series? Are they basically the same thing?

Aslong as the F series mod is detailed to work with 3.0 it is the same thing as the X series.

Most of the mods do just that.

Tell me one mod? Most of the mods are just covers over the top of the original system. I still have to find a new cooked firmware for the damm thing. Only leetlauncher is on the right way, but still waiting for a new version.