I started with the H2D/22 Mark ... trust me, for the way you shoot, and the print size you want, it'll be fine.
Get the H3D/22 and the 28 ... the lens is great !!! You can always upgrade later if you want ... maybe to a H4D/54 : -) I upgraded from a H2D/22 to a H3D/39. An extra battery or two is a good idea if you go out for a long day of landscape work.
If you don't have a source for a reseller I can enthusiastically recommend Jim Arnosky at City Lights Digital ... best after sales support I've ever experienced ... even at night and on Holidays via cell phone. He is a photographer at City Lights Stage so he really knows what he's doing as well as being well connected at Hasselbald. Tell him Marc Williams sent you.
jim@cldigital.com
BTW, if you shoot landscapes during winter, you may want to get a film back also ... none of these digital backs made by anyone are recommended (or actually work) in really, really cold conditions. I have an extra mint H film back for sale if you decide you need one.
These backs can also be used on a view camera ... I use mine on a Rollie Xact with digital lenses ... now that is spending time composing and sweating the details like the days of old.