This is what I have hotkeyed.
1. (or left) Bow
2. (or right) two hander
Selecting a spell to my right hand out of the favorites also brings up the most recent left hand spell that was selected.

I went into the main magic menu and selected ebony flesh to my left hand, then exited the menu.

Out of the favorites I selected grand healing to my right, then exit.

Then i hit left or right to equip a weapon, and if I go into favorites to select the grand healing to my right hand, my left hand will still have ebonyflesh. I also used courage in my left hand this way as well, when I had Farkas as a companion. I kept his courage up and healed him as well then went back to battle with hotkeys 1/2.

I also found that this applies to a shield if it was the most recent left hand equip out of the menu. You can use this to pick up your defense as you use a spell in your right hand, then go back to 1/2.

After discovering this method, I almost never have to scroll through favorites just to get to certain things. If I have one of my weapons equipped, I just hit favorites and grand healing is always at the marker, always.

Basically any left hand selection out of the main magic/items menu will always defauilt to that if using a favorite for right hand.

I cannot say if this works for other types of combos, but my use of these spells/items specifically works well for me.
Does anybody else do this? I think this would work for PS3 as well.

This is a small, but significant, part of the reason I love 2-H weapons so much.

I set 1 (push to right) as my current 2H weapon. I set 2 (push to left) as my current bow. When I push again in the current direction (unequip) I have my hands set with my spells -- often double healing, but sometimes other spells I find useful. Works like a charm, as you point out.

This is also why 1H weapons can be a tad bit annoying. I can have a 1H + spell setup I like (say, dagger and a conjure spell) but I switch to bow then, later, unequip the bow and cast some spells and then go back to my dagger preset. When I go back the conjure spell is gone, replaced by whatever else I more recently had in that hand's slot.

Yes i actually forgot to mention that as well.
if you hit the same direction of the equipped weapon its the same as going back to the most recent spell or spell shield combo.