Like many other people here, there a lot of missing weapon types that i'd like to see added to the game (spears, crossbows, flexible weapons like flails or whips, javelins) and it would be cool to see those in later chapters, but what I'd really like to see is some of the missing play styles filled mechanically, rather than just new graphics.
Specifically I personally really wish there was a stamina based option to heal your group, but there are several other play styles that aren't represented currently in the game. Such as magicka based melee weapon, a one handed magicka option, or a ranged stamina based tanking weapon. Some of those would obviously need some new weapon types and/or skill lines, but I think there is an obvious where some of those mechanics could be inserted into the existing skill trees.
Specifically, the "One Hand and Shield" skill line is the only existing line where you can equip multiple weapons types which have no effect on gameplay at all. In the dual wield line, two handed line, and destruction staff line changing your weapon has a passive effect on your play style, and I think adding that diversity into the one handed shield line would be a great way to cover some play styles that don't currently exist in the game.
Because my personal preference would be for a stamina based healing item, I would like to see one of the weapon types (mace?) change some of the active skills to provide some healing. Perhaps low slash could apply minor lifesteal instead of maim, or charge could target an ally and apply a damage shield.
Or for those into the melee magicka role perhaps the dagger could allow the abilities to scale on spell stats instead of weapon stats. Or perhaps the dagger could become a thrown weapon to allow for ranged stamina tanking (though I think a javelin and shield would be better for that).
What do you guys think? Are there other missing combat roles I didn't think of? Would the tanking role of the 1 handed and shield line be too adversely effected if one of the weapon types changed your role?