I still say that the enemy fetchlands will be printed in Dragons of Tarkir, and the ally painlands will be printed in M16, due to the fact that those two sets will be their own "block" under the new rotation schedule, and I am assuming that they will want each block to have a rare dual land for each color pair.
Concerning protection, I believe the problem Wizards has with it is not so much power, but complexity. I remember when I first encountered protection when I first learned Magic, I thought the guy I was playing against was bullshitting me. My creatures could not block it, but it could block my creatures? Not only could I not deal damage to it, but I couldn't even target it with spells? Even when I was playing a Khans draft just recently, I was amazed at how versatile Feat of Resistance was.
I think the best move would be to split protection into multiple abilities
* Resistance to X - This creature can't be dealt damage by X. Variants of White Knight and Black Knight that just had resistance to black and white respectively would actually be able to clash, though their battle would be never-ending.
* Can't be enchanted/equipped would probably best be dropped, considering how rarely it isn't covered by "can't be targeted". It can be explicitly spelled out if necessary.
* Can't be blocked can just be written out as "can't be blocked by X".
* Hexproof from X - This creature can't be targeted by X spells and abilities an opponent controls. This isn't the same as how protection works, but I think it's a good way to have a "weaker" version of hexproof and would make it so that there is a net addition of 0 new keywords, with resistance replacing protection.
So Black Knight with hexproof would be like:
Slightly Stronger Black Knight - BB
Creature - Human Knight
First strike (This creature deals combat damage before creatures without first strike.)
Resistance to white (This creature can't be dealt damage by white sources.)
Hexproof from white (This creature can't be the target of white spells or abilities your opponents control.)
Black Knight can't be blocked by white creatures, and can't be enchanted or equipped by white permanents.
2/2