I think its the size and form factor of what they are going for. It seems they need to keep it thin as well as a size that is manageable for the type cover.
This is true to a point. But in general, trackpads are, at best, pretty meh in Windows world. Maybe things'll improve with Win10, since MS is enforcing a standard set of gestures. But that still requires the OEMs to make a trackpad that's worth half a damn before it can be taken advantage of.
I just got a new rMBP and the force touch trackpad is a delight to use. It's super accurate, effortless clicking, and feels amazing with all the gestures.
Since I'd be using the pen more often than not, I'm pretty dead set on getting a Surface at some point (or possibly iPad Pro depending). But if I were in the market for a good old fashioned regular laptop, it'd be a Macbook. Because of their trackpads, you don't even have to think about using it. You put your fingers on it, and it does what you expect it to do, smoothly and efficiently.
Contrast this with using a Windows 8 laptop, where I felt like I was putting my fingers through a particularly cruel game of Twister, and kept constantly calling up the charms bar by accident. It made me want to punch something.
