It seems like syntacticians, of both mathematical and generative stripes, are constantly hunting for a new and improved syntactic theory. But I'm not really sure what we are supposed to be looking for. Surely now, it is established that any theory capable of generating languages of sufficient complexity is capable of "capturing the data" or describing it or whatever. Yet syntacticians still publish papers where they demonstrate that some new notion or theory is capable of deriving some fancy piece of data that somehow eludes the others. Is this really what they are doing? Because this seems like a moot argument.
It seems to me that, if there is to be any rationale for improving syntactic theory, it should be something like cognitive plausibility or computational effectiveness, or perhaps even theoretical elegance. I don't know what people are driving at, because the desiderata of a better syntactic theory are almost never discussed. Should we all know what we are seeking? Because I'm not so sure anymore, and thus I am not convinced we should continue to hunt around. For the moment I'm satisfied that type-logical grammar is capable of deriving everything that needs to be derived. Am I wrong?