This seems to be a pure DX or FX decision. Unless you have a need/want to shoot both, the transition will not benefit you. In your position, I would choose one or the other.
I ultimately went with the D600 and kept the D7000 as my backup. Sold most of my pure DX lenses and only kept the 16-85. Bill is correct in my opinion, there are some nice wide DX lenses.
As far as FX, you will definitely increase the bulk of your kit significantly (physically and financially) if you go with the top of the line lenses. I am greatly enjoying the new 18-35 for my landscape work as well as a couple of very small primes. These keep my FX kit light and comfortable for hiking.
Bill makes some excellent points, however, having owned both D300s and D7000, they are very different cameras in terms of feel, controls, etc. While the D7th is an upgrade of sorts to the D300, I don't look at it as a linear upgrade (ie.D7000 to D7100).
IMO, decide which direction you want to go and do it. You never know if and when new models will arrive. Enjoy the moment. If you need/want FX, go in that direction with the D600 or D800. Without a compelling reason for FX, get the D7100 and ignore FX.