Y'know, everyone thinks they have good intentions. Have you ever met anyone who said, "I'm here to break stuff and screw the world up"? No, of course not.
I'm thinking you don't actually need good intentions to do good works. Actually, good intentions by themselves don't seem to accomplish much of anything.
Here's the top three virtues I'd look for in someone to actually achieve good things.
Strength is the virtue that's required for all other virtues. If you're not internally strong, you get easily swayed by opinions, social pressure, culture, and things like that. It's hard to hold on to virtues if you're not strong when you're in the crowd.
Long-sighted (as opposed to short-sighted) means a person is thinking 10 years, 20 years, 50 years, 100 years, 500 years out when they take actions. Many people don't think beyond the moment.
Pragmatism means looking at what actually works in the real world, studying examples and history, and going by results instead of intentions or emotions.
I think those three, combined, will produce much better and healthier results than even the best of intentions. For instance, whether a person is selfish or unselfish isn't all that important to me - so long as they're strong, long-sighted, and pragmatic. If you're long-sighted and pragmatic, you generally look for people you have an ongoing relationship with to win, and you realize it's stupid to screw someone for a short term gain. The strength there is the icing on the cake - it means you treat people well even if someone else close to you goes hostile on them or pressures you to wrong by them.
See, I don't think there's any fundamental conflict between spending your time bringing the world you wish to see into existence, doing good works and achieving the objectives you've got personally. Whenever I hear someone get criticized for being selfish, usually you can replace "selfish" with "short-sighted" if the criticism has any legitimacy at all. Treating people well, doing good things, and generally conducting yourself honorably is the way to personal success as well as living in the best possible world. The strong, pragmatic, long-sighted man knows this.
Incremental improvement, not doing long-term destructive things for short-term gain, self-control, willpower, discipline, focus, planning - all of these from the mix of strength, long-sightedness, and pragmatism. If you're long-sighted, pragmatic, and strong, you start learning and training and planning to reach your objectives. All the other good virtues - charity, service, loyalty - seem to flow naturally from strength, pragmatism, and long-sightedness, because in the long run, doing those things serves the individual and the world at the same time.
Short-sighted good intentions or idealist, unpragmatic solutions have brought a lot of hell and misery to the world. Take the strong, long-sighted, pragmatic guy every time over the short-sighted or non-pragmatic guy with good intentions.