Sponsoring individuals registered for a charity event

Hi there, to anyone familiar with all the plugins WPMU Dev has to offer (and more), I need to create a fairly specific site and wondering what the best combination of plugins/themes would be to accomplish it. It's quite a lot and don't even know if it possible, but hoping to at least get something close.

This is what I need to accomplish:
- A big charity event with all the information on it
- Ability for people to register (and pay) to join the event
- Registered attendees to be listed publicly on the event page (a sort of RSVP/guest list) that is public to everyone viewing the event
- Ability for other people to sponsor/donate to an individual who is registered for the event (online payment and/or offline payment)
- Totals of payments for each participant visible on front-end, as well as overall total for the entire event

Debating if it should be an event theme or a charity theme, and then use plugins to customize, or maybe buddypress could handle a lot of these functions along with some plugins on here.

ANY input or suggestions would be very very helpful! Thanks in advance to anyone with their suggestions.