You have not quite accomplished what you set out to do. That is to say, you have more or less agreed with my initial statement of Objectivism being centralized around greed. Now, we can call it a pursuit of ideals, but the ideals are about rational self-interest and the absolute absence of altruism. Ultimately, it is the pursuit of doing what's best for you and only you, with the hope that society doesn't fall apart in the process. This is not conducive to medicine in my eyes, and I have no reason nor need to be tolerant of it (much like I would be intolerant towards, say, a KKK member, or someone who spent their time fighting against gay rights). Besides, every Objectivist I have ever met had a misplaced superiority complex and a complete lack of social tact. It seems Objectivism is an excuse for complete douchebaggery on the part of its adherents.
And the Marxist question was a joke. I'm sure there are a few still around (in fact, there's a Marxist trash-paper that gets circulated every few months at my university), but the main thrust of the political movement died when the USSR collapsed and the world got to see, for the first time, what the ideology led to. The failings of the system are irrelevant, and needn't be discussed here. That being said, the few Marxists remaining do so because of compassion. Marxism, while inherently and philosophically flawed, is ultimately an ideology based on equality and working for the good of others. Objectivism and Marxism are both ideologies, sure, but they're as far apart as could be. As for your opposite ends thought, that may be the case, but the end that Objectivism deals with contains a very small percentage of society, while the end that Marxism traditionally dealt with represented a very large proportion of society. Irrelevant, I know, but worth noting all the same.
Of course, regardless of the ideology, I'd have to question anyone who actually enjoyed the Fountainhead enough for it to change their philosophy, as it may have been the most poorly written book I have ever had the misfortune of reading.