I recently said, "Maesters will probably become the next Wildlings" on the Maesters thread. What I meant is I'm concerned they will become powerful enough to dominate the environment. Maybe not them alone, but them and the Chains seem worrisome. The whole cycle is dedicated entirely to them, which pretty much ensures there will be powerful Maester related cards if history has shown us anything.
Maesters are cool, but I'm really not that amped up about them. Six months of one theme is just really boring, and has potential to be disastrous. The theme is more likely to be really good (i.e. Wildlings) or really bad (i.e. Night's Watch), than being balanced. I'm sure it wont be 100% Maesters, but the great majority of it will be.
Personally, I think FFG has its design scheme backwards, and are doing a great disservice to the game by pushing the mono-themed cycles. I don't have any hard facts or numbers to go by, but intuition and general conversation has led me to conclude that people are more excited about the House Box Expansions than they are with current CP cycle system. I'd take a new Targ, GJ, Lanni, and/or Martell Box any time before wanting to see a whole 6 months of just Wildlings/Night's Watch, Maesters, Armies, Kings/Queens, Lords/Ladies, etc. I'd rather have 6 months of improving Houses in general (i.e. Clash of Arms) and build on specific trait themes through expansion boxes. Actually, I'd still rather the boxes build on the Houses and just scrap mono-theme expansions/cycles. Themes are cool, but Thrones was at it's best right before white bordered cards were introduced, when each House was good and had in-House solutions. We're never going to bring the game back to the state it was (in terms of being really good and balanced) if we keep on wasting half a year throwing a single random theme or two into the game.
If it wasn't for the House expansion boxes (even if you decide to not count the Greyjoy and Martell boxes as actual expansion boxes because they were necessary due to being excluded from the Core Set) this game would have fell apart already. If it wasn't for the Targ box coming out next (every bit of paraphernalia has suggested it will be) the game would eventually fall apart, or at the very least Targ would remain the clanky House it is for a MUCH longer time. The only reason why Targ truly became competitive was because of Wildlings. Targ Shadows can be pretty good, but it's not good enough. It took some random theme to make Targ competitive. Targ and Wildlings: where's the thematic sense in that? If there is one person who believes that 6 months of Wildlings and Night's Watch did more for the game than 6 months of general House improvement, I'd love to hear you're reasoning because I can't think of one good argument to seriously support that belief.
It's because of this that I said Maesters will probably become the next Wildlings. I just don't find it interesting to have to meta against a single theme because the card pool has been inundated with 6 months worths of cards that support it. The game could never have had Wildings and been fine. The game could never have a whole cycle dedicated to Maesters and be fine. The game could not have in-House problems not be addressed (a.k.a. House expansion boxes) and be fine.
I don't need nor want Great Maesters. I want Great Houses, but I don't see the next half year fulfilling that desire nearly as well as it could have.