I wrote a nice article in another thread but, I may as well put an abridged version here.
I completely agree that the offer should remain open indefinitely. (At least as long as servers are up.) It seems like a wasted opportunity on EA/Pop Cap's part to discontinue it. Some people say they would pay anything. That means even paying for GW1 coins to grind to 313. (Sounds like good money to me.) I also think it is a very poor business move to lock anything away behind a limited time door. Especially when many games get a resurgence in sales once the price goes down. (IE right about now.) Its just begging for unhappy customers.
I will say that I understand the point of view of people who play for fun. I myself played GW1 many, many hours. (I would bet money on it being over 1000.) But, since the challenges were the only thing that made the grinding interesting I made a point to avoid using skip stars. (Under 5 in fact, and those were only because my brother got impatient.) Never the less, the requirement for the Unicorn was 313. And, while I personally disagree, I would rather that be the requirement indefinitely over nothing at all.
I do also want to say that it was uncool to put a time limit on such a large grind. I may not have gotten all the way 313 but, I know the time it took to get to the 100-200 something I did reach. (Really wish I had XBL still so I could look it up.) For anyone with a life, I can't imagine the stress that would put on them. I saw testimonials of people doing it in a month playing hours per day. I will say again, that is uncool. If it was an indefinite offer it would have reduced a lot of stress for a lot of people. (This goes for all limited time things.) Just something to think about in the future Pop Cap.
As a last note, I have a differing opinion on the transfer of older accessories and variants. It is terrible to put effort into these sticker books only to have to start over in addition to the new stuff with each installment. More importantly, the inability to transfer variants undermines the backwards sales. Think about it, GW1 = Unicorn in GW2. But, if GW2 doesn't allow transfers to GW3 then the need to play GW1 is lost. If closing the servers is their goal it would make sense. But, when something like TF2 has had servers for over a decade it looks pretty poor for the competing origin/EA to drop servers after only a few years.