So, uhh, are you good and comfortable at using the mouse with your right hand? If so you have no reason to use your left. I have a left-handed friend who has always exclusivity used his right for the mouse. Ain't no law saying your mouse hand must be your writing hand. Not to mention the benefits: it's the default setting on any system, and there are lots of great quality asymmetric mouses that only fit the right hand.

I'm not trying to change you, by all means if you like the trackpad more power to you. Just curious why you'd try to mouse with your left if you've already learned to use it with your right.