While I want campaign finance reform, it's been pointed out to me that it will likely be infeasible to give everyone who signs up money from the get go, so there has to be some process to prove one is a viable candidate. If that means getting some signatures or something like that, a candidate must already be able to coordinate volunteers (with paid staff, I imagine), so there's already one point where having someone invest in a candidate can give them an advantage. Plus, the parties already have this infrastructure in place, so the Dems and Repubs are already ahead. We need some finance reform, I just don't know what that full picture looks like yet.
It also doesn't completely remove the profit motive, like you said. Politicians can still help land contracts enact favorable regulations, or dismiss unfavorable ones, and then find themselves landing in a cushy job in those industries they gave so much to. This would say maybe you don't want politicians leaving office to indulge in some post term conflict of interest, but I don't think there are a lot of people that believe in keeping our current politicians around that long. It's kind of tricky :[