When we left the Mormon church my wife and I decided instead of the tithing we were paying, we would each support a single charity with regular contributions, she chose "Save the Whales" I choose "North East Air Ambulance service".
I don't think I would change if I had more to give, just a little more a little more often.

HEIFER International, ACLU & Smile Train, which I give to now, I would just up my giving.

I would like to invest in an online learning platform like Coursera, and invite everyone (in particular those that either don't care for college or can't afford it) to take as many courses as they'd like to. Education is important to any civilized society.

That, or supporting a group dedicated to women's self-defense, such as paying for self-defense classes etc. When I was a teenager, was involved in Karate classes, and when I reached black belt had assisted my sensei in teaching classes, and twice every month there were special classes just for women, and had enjoyed helping to instruct those classes.

Planned Parenthood, ACLU, anything animal

Special education-funding for special needs children
Cancer/leukemia research
Music and Drama Programs for children
Animal Rescue

I'd invest in green technologies. I'd donate to the Freedom From Religion Foundation.

I would contribute to 3 types of causes:

1. Those which protect our civil and constitutional rights.
2. Those which mount transferable programs which empower and enable people to develop and sustain themselves over time.
   3 Those which invest in developing technologies which support ecological and climate sustainability.

I would donate to the following : Population active international ,Environmental Defense Fund, Wildlife Conservation Society, P.E.T.A., Greenpeace, Sea Shepherd conservation society, Sierra Club,Rainforest Action Network , to name a few

I'd like to be in a position where I could purchase bad student loan debt (pennies on the dollar in most cases) from a collection agency, and then forgive it... just erase it. Remove it from their credit record.

I would want to contribute to a variety of causes, but right near the top would be environmental and civil rights promotion/protection. Specifically, LGBT homeless youth shelters and mentorship programs, especially in deep red states that tend not to give a shit about these abandoned kids.
Secondly, something to promote adoption of solar and wind power, including upgrading of a smart electrical grid.

Can't truthfully answer that. I don't know. I would probably hire people to do that for me as a tax write off. Yeah.... that's how you stay on top.