I remember getting hit with the empties from a Ruger 10/22 when I shot one as a child, I have not shot one in a long time so I can't really say how much it would bother me now.
That being said, I would love to see a Ruger 10/22 with left ejection and bolt handle as it would make it perfect for me to shoot as a left handed shooter.
I can't find left handed bolt action .308 that I like so I plan to build myself one around a custom left handed receiver and once i finish it I will never get rid of it.
I would like a left handed revolver, basically have the cylinder release on the other side and have the cylinder swing out to the right. Normally for everything other than pulling a trigger or bow string I am right handed. With a revolver like I describe it would make reloading it a lot more comfortable. Maybe I will get a Colt SAA one day as it is actually built to be used with the left hand.
I wish there were more left handed guns in general, it isn't just a lack left handed semi-autos as it is a general lack of left handed firearms.