Agreed. I don't think it's that great. Not that it's bad either, but there are better artists out there. And Land is largely criticised for making characters look the same, and mimicking/recycling images in his artwork. I do think that his art kinda works, and it's not terrible, despite being lazy and uninspired. But that's another issue.
Pak hasn't done the Weapon X roster any favors. Domino is a cheap trope reduced to a gun-toting money-hungry merc. Sabretooth is a mess. Lady Deathstrike doesn't do anything. And Warpath for some reason can now fly and has a healing factor. If the book isn't ending, then I'd rather he gets characters he can write well.
Absolutely. Without some of the 'big' characters, getting a roster of relatively unknown characters to stick just isn't going to happen. We all have our favorites, but the harsh reality is that a number of us won't ever get solos for our faves, or a team book where we like the entire roster. Cancellations are pretty regular in comics these days, and without decent sales, Marvel will have no hesitation in dropping a book. So yes, it's necessary for mainstream characters to carry the title and bring in casual readers who wouldn't otherwise pick it up.
AFAIK, the sales aren't coming from longtime X-Men fans. Guggenheim doesn't show an awareness of the characters histories or personalities, and continuously uses the same boring story tropes. I don't know who is buying copies, but it sure ain't me. Can't wait until it's canceled so another writer can save Ororo & Kurt.