PErsonally :
Return of :
1 Spears
2 Medium armors
3 Piecemental armor
4 Improved crafting system featuring combos of styles and materials not just race
5 More realism and a hardcoe survival mode
6 Dark dungeons
7 no streamlined dungeons
8 better character creation
9 more epic landscapes
10 tessellation snow , deformable surfaces and proper animated seas
11 navigation , boats and sailing
12 proper chart riding
13 return of classes systems
14 return of the attributes
15 More long quests and more realistic
16 Realistic realization of the world , with interactive environments, like give flame to wood , see it destructed, etc .