I don't put myself on the political spectrum -- but I do pay attention to politics. Most of what I do is tell other people why their idealism won't work and spread general pessimism
Or, in other words, my political stand is realism. I wouldn't mind involving myself in politics, but I still wouldn't choose to take any particular stand; I prefer keeping myself open, since I tend to like different things on different sides, and like working more on a case-by-case basis
I promise you that you can pigeonholed as much as the next person. Maybe you lack enough awareness of yourself, or maybe you aren't aware enough of other ideologies to have enough perspective, but it can be done. Your "openness" is really trying to conform things to a particular way of thinking, maybe a way of thinking that is not mainstream to some degree. No one is so clear sighted and intelligent that they can rise above systematic thought to see straight at the truth, despite what many people tell themselves.
As for "realism," I consider myself a materialist. I think that there is a material world and that it develops independently of any one of us, and so I call myself that. But I cannot say "I'm a materialist" and call that the end of it. There's different kinds of materialism, and I subscribe to one of them. The other ones work differently, since they serve the interests of different strata, and I am concerned with the majority of the world's interests.
I would say, though, that confining oneself to criticism of the status quo amounts to idealism (the opposite of materialism) if there is no route forward. You see something wrong and don't like it because it doesn't bode well with you, and so you challenge it, but that's it. At most this leads to trying to apply various principals/ideals.
At worst this leads to manipulation via various kinds of conditioning, through education, the media, etc that the status quo can throw at you, and you end up on the wrong side of the fight without knowing it, against the majority of the world.
I would say the "Free Tibet" campaign is a good example of this. Actually, I would be very glad for Tibet to achieve independence in a progressive context, but the movement is already rather reliant on foreign powers, and I imagine Tibet would be completely reliant on western powers if it achieved "independence." Tibet would have to trade material support for a loss of its independence, and its loss of whatever short lived "independence" it could have would then be used to undermine China. I would say that many of these "Free Tibet" types are not completely mainstream in their political thought, and would consider themselves critical of the mainstream to a large extent, but they are still able to be brought on board in promoting the state interests.
Still, sometimes certain kinds of idealism will be more progressive than certain kinds of materialism. I would rather you adopt a general pessimistic attitude than get on board with the Republicans and Democrats. Even a Free Tibeter often will have her heart in the right place, even if what that means practically is very limited. In many ways, I'm rather pessimistic myself, but I do think there's a way forward. If you don't see one yet, keep looking, and remember to approach the world as it works
Of course I say all this without being very familiar with your way of thinking, so I'm speaking in generalities. If I were intimately familiar with how you think, I could be sure to say something more relevant to you in particular, but maybe this will be useful to someone still.