Honestly going to FF earlier might benefit your landscapes. It's amazing just HOW much wider my lenses were on a FF body. If you know how, I might also recommend taking shots and stitching them on photoshop (there's an automate tool that will do it for you if you're lazy).
For example, at the time all I had with me was a shitty ass D-40x (got the job done so don't hate) and my 50mm 1.4 AF-D. And I took this. Came out with more resolution than a d800, bitches.
I cut it like that so it could be printed in three 4ft by 2ft sections to line my hallway under three spotlights. Final composition was 9 photos stitched to a canvas size of 21,000 x 3,000 or 63MP. So I guess all I'm trying to say is that sometimes landscapes can be achieved through different results and not always a high dollar wide angle. However that way is more common and more convenient. Just trying to provide a different look on your current setup to get HUGE prints