For a long time I've had the feeling that there's a bias in contemporary philosophy against arguing for 'big' positions--the kinds of positions those who hold (or discount) hold (or discount) in a fundamental way. The thought is: if you give an argument for one of these positions, the only people you convince will be those already convinced.
What remains to philosophy is--must be--to only solve problems within these fundamental framework views. But that makes it difficult to ever interact with those who reject them, UNLESS your M.O. when interacting with them is to always accept others' presuppositions and to try to work things out within their views.
That's all well and good, I suppose. But it seems to be ignoring a herd of elephants in the room. (That, and I'm absolutely terrible at accepting presuppositions I object to.)
I think it's really bad for philosophy not to argue for big positions. I think that there's a really interesting way, though, that a lot of mid-level problems turn quantity into quality. If you're solving a lot of problems or raising a lot of interesting questions, those solutions, those questions, turn into material, and material eventually becomes a way of persuading people that there's (almost literally) stuff there.
This is certainly my experience of all "conversions-to" that I have undergone. I think I know the whole domain that I am interested in, but then there's a thing in a completely different domain that sounds kind of interesting and I pull that thread and other things come with it, and then it turns out there's a new domain.
I think chess is all I need, and I look at bridge or go, and there's some interesting strategy going on there, and then the game starts looking interesting and then it starts getting real.
So I think I don't get into things by accepting presuppositions (unless that means "rules of the game," not foundations of the world or something) -- I get to what you might be calling presuppositions by finding certain claims interesting, or finding it interesting that some people find them interesting, and then eventually I (sometimes) start seeing why.
I hope that makes sense?