I too find that the DP Merrill is a specialty camera. Most of the time I use my Canon 6D, and live with the DR deficiency via ND grads or multiple exposures. Canon 5DSr has happy users, and should be among the less expensive high resolution cameras available now refurbished or used. I haven't yet jumped on that band wagon, since for my small prints, 20 MP is fine.
The Zeiss Distagon 21 f/2.8 is a lovely lens. Digilloyd has a bunch of reviews of old and new Zeiss lenses on his pay site. I have heard from former Distagon users that they are happy with the results of the Canon 16-35 f/4 for landscape. 16-35 f/4 L IS and 70-200 f/4 L IS II or III make a pretty versatile landscape kit, if you like zooms.
My FF landscape/macro kit is the Zeiss Distagon 21 f/2.8, either the Sigma Art 35mm f/1.4 or the lowly but light and good Canon 40 f/2.8 STM, and the Voigtlander 125 mm f/2.5 1:1 macro. Plus tripod. Every once in a while I will dust off a Merrill if I want to travel light. For some reason, I like limiting my options some.