I would look at either the 6D or 7D. Depends on if you want a full-frame sensor or not. The body-only prices are usually under $2000 USD, probably around $1500 or so, depending on the model. You’d probably want the Mark II versions that are out now.
If you ever take any videos, the 7D has much better recording and subject-tracking...at least that was the case with the Mark I specs. It’s more versatile than the 6D, but it’s not a full-frame sensor, which mostly just has a greater impact in low-light settings. But if you’re mostly shooting nature and daytime landscapes, either one is good and the 7D should give you more versatility for shooting and filming.
Thanks for the input @ats-david. At first I was actually considering the 80D as the specs seems pretty good on paper compared to 7D and I could get the 24-70 2.8 II for a decent price.
But yesterday I went to few camera shops to get a hands-on experience and I must admit the 6D mkII feels great and I think it's time to upgrade to a full frame goodness anyway.
The only negative thing I can see about this camera is that it's shutter speed + buffer comparing to other brands, but not to say it's a problem that will put me off!
The 5D mk iv is a dream but it's just too much for a hobby!