I have an idea on dual wielding controls, since for me a feature must be easy to control.
As dual wielding places a weapon in both hands, the left trigger will now be used for swinging the left weapon. On the PC the buttons switch, with left click now applying to your left hand weapon and right click your right hand.
Blocking is accomplished by pressing both attack buttons simultaneously. However, if one is to let go of a button (say, the left trigger), but still hold the other button, then the other weapon will still be held up, allowing the player to keep an opponent in lock while still using one of their weapons to attack. Letting go of the blocking weapon's button lets your guard down completely.
Due to the player's hands both being completely filled now, the left shoulder button (which in Oblivion is grab, but, as I have mentioned several times before, should now, when used against NPCs, act as a grappling function) now no longer grapples with one's hands, but with one's weapons. When pointing one's cursor in the general direction of an enemies weapon, the context changes to become a parry. I'm not sure which I like more; The grapple button could be held down, then one of the two triggers pressed to parry with the relevant weapon, allowing the other to be open, or the grapple button would simple parry with the right handed weapon always. The former is more complex but allows for more flexibility in maneuvering yourself and your opponent (parrying with one's left handed weapon could force an opponent to stagger to the player's left, positioning them against a wall perhaps. Always parrying to the right could cause problems) while the later lacks options but is much simpler to achieve.
When pointed at the body of an NPC (context also changes depending on which body part one is pointing at), the weapons are now used to grapple. Grappling at the chest would allow one to grab an enemy around the torso. Pressing attack would then allow someone to slice at their chest or back (depending on whether you were in front or behind them). Grappling the head is difficult to do, but success allows one to attempt to slit the throat or attempt a choke (if one had blunt weapons, like a mace). Grappling at the lower hands of an opponent would allow the player to cause the enemy to drop their weapon by cutting their knuckles.
As with all grapples (both with one weapon, two weapons, or no weapons), pressing the relevant direction on the control stick causes the player to attempt a throw or take down.
On the subject of grappling itself: I believe it should be available to most fighters, despite being part of the Hand-to-Hand skill I think grappling should also be affected by strength and agility, so those with high strength would have trouble succeeding a grapple, but once they had their enemy in one they would have little trouble keeping them in it. Those with high agility would have little trouble succeeding a grapple, but have a lot of trouble keeping them in it, so they would have to act quickly (usually attacking a letting go. Those with high agility are most likely thieves or assassins, so a slit throat should be fast and not hard to complete without the grapple being broken), although throws would be difficult for them as strength would govern how well someone could throw the enemy, if at all.
The main reason I want functions like grappling, parrying, shield bashin (which I did not go over, but have before. It would be very easy to do. While holding block, press attack. Rather than swinging out of a block, like in Oblivion, instead the player would bash with their shield. Hell, they could even be allowed to bash with the pommel of their weapon, so long as they were no dual wielding and had no shield equipped.) is so that fighters, especially hand-to-hand characters, which are notoriously boring and difficult to play, could be more fun, less straight forward, and have more options available to them so that they find themselves in much more complex situations.
Wow, I really let myself go. I expected this to be much shorter. Rant over, I suppose!