I've never liked the Canon grid screens too busy, and for my use I'd rather not get a split screen. I have a Maxwell rule of thirds in my 645 AFD and had one in my 5D and 4x5. I have been disappointed by how easy the Maxwells are damaged and poor response to emails so with my 5D2 I'm trying the Brightscreen just for the rule of thirds grid, an expensive option but what the "H". It's just me and a quirk I have without grid lines I get too many horizons off just a degree or two, enough to notice when you look at them later, the grid solved the problem.
Marc
Photoshop solves that problem too, or mounting. But I see your point. It's your comfort zone and it makes your life more pleasurable, so why not just do it? I use to be bothered by that too. I would obsess over it. Now that I have a RRS ball head and no way to level the camera w/o a hot shoe level, I just eyeball it, usually withing a couple degrees, and then straighten it post.
I'd still like to know how much if any they darken the screen or need exposure comp. The Canon's make the screen darker on everything except fast lenses, and then I think even 2.8 lenses get a little more dark.
Do you all not trust the autofocus on today's top end cameras?