Well the game only has so many mechanics - trade, missions, mining, bounty hunting/combat zones and exploring. The game has 6 ranks/ratings (I included CQC). This actually has not changed too much from early days.
If you have done all the mechanics to death then have a potter around on a surface of a planet and explore the new mechanics on the surface in 2.0 seens like something to do. Then I expect you should put it away again.
Exercising any of the mechanics without a context and a group of chums with similar objectives seems remarkably boring to me. Early on we all share the same objectives as they are ranking based as a context for our mechanics use. Then you get to a point where you are "happy" with your ranks, or rather your current position is acceptable compared to repeating the mechanics for the next rank. We all at some point share the desire for a certain ship, so that drives us on.
There comes a time where you cannot find a new context or drive to use the mechanics - sounds like yo hit that bit before your break (I hit in Feb last year but my rank requirements were very low!) I would suggest you find another context, such as Powerplay, or the BGS to gives the mechanics some context - also some variety. This is the most Vanilla "more to do". Alternatively sounds like your rich, why not help new players or becomes a fuel rat - the Anaconda is the best ship to be fuel rat.
Protecting Nubies you can pass on your trading skills, and their will be combat as you protect them. Fuel rats looked really good fun from Ed's stream.
I am sure there are many more things, there appears to be groups of players for just about anything, but I think you have moved beyond being driven by ranking or next ship, there is no "prescribed" next phase you need to go find one that suits you.
Simon