I would stay away from Alcans - most people say they are too short - I have no personal experience beyond seeing pictures from several guys here on MUD with frustrating experiences (because even though the springs didn't fit properly, Alcan claimed the springs were custom-made and therefore couldn't be returned)
but what I do have experience with is the following: all leaf springs will eventually sag - which means the lift they can provide will become lower. So why not start out with a decent lift, so that when the springs settle, you can accommodate your tires comfortably - in my estimation, a 2" lift will be almost close to flat in a few years
when I was looking at new springs several years ago, the Man-a-Fre Mohave springs had not been released to market yet, but were touted to be providing a really smooth ride - so if they are available, I would get those now - (BTW, if I remember correctly, Dave Gore was involved in the development of these, and in my 15 years of experience with his stuff: it just plain works and never breaks)
my truck had Skyjacker 4" lift springs on it when I got it, sagged down to more like 2.5" in actuality - Skyjackers are purported to be relatively stiff, but when combined with fresh bushings, I found the ride of my truck quite smooth - and when I broke a leaf and had to get a new set, I went with Skyjacker 4" again - (like I said, the Man-a-Fre Mohave springs weren't available yet at the time or I would have gotten those) - and I wouldn't hesitate to get 4" Skyjackers again these days
simple reason: availability, and the fit with the bushings Skyjacker provides for them as well; you can have all Skyjacker products shipped to any 4 Wheel Parts (and if you so wanted, have them installed there) - and although I have absolutely no use for the religious pamphlets Skyjacker includes in all of their shipments, it felt good to me to support a local business in a state I live in (Skyjacker is located in northern Louisiana) - just as I would have felt good to buy the Mohave springs (and support 4Plus=Dave Gore in Arizona)