Upload & Sell: Off
I am not a big landscape shooter. There are some amazingly dedicated shooters who get up before first light and/or hike to exotic locations, people who travel and return to the same spot day after day. Those are the people who make great landscape images... I won't ever have the time or patience to do it.
What I will say is that I have heard of large grad ND filters with handles that people free handhold in front of lenses. That is the route I would take. Polarizers will do weird stuff to skies when you are wider than 24, so I wouldn't use one anyway. I have a 77mm pol that I can use on my 24L II if I need it.