Solmyr

Played through this mod in god mode via using Alternate Start and starting as an Imperial/Stormcloak soldier. From what I can see, the main things it adds are battles for the cities (rather than using small fort battles to conquer holds), the ability to lose, and lots more spawns. Most bugs could be recovered with via reload, but the last two Imperial assaults (Winterhold and Fort Amol) somehow caused the Imperials to be hostile to me as well, so it was rather odd with both sides trying to kill me. The mod was tested with a relatively light mod number, I'm guessing it may stutter more with a larger load order. It may also clash with creature-spawning mods if they happen to spawn in the same areas where this mod's battles take place (though I guess that would clash with vanilla too, as the battles out in the world take place in the same forts/camps). City battles may conflict with heavy-duty city-altering mods. The huge hordes spawned by this mod may also stress your system, although corpses disappear quickly as in vanilla. I'd also expect you need to be pretty high-level to have a chance of winning, as the NPCs spawned are quite tough and there are dozens of them. The large amount of spawns was the only thing I didn't like about this mod, otherwise it looks very fun and solid.

By the way, what made you switch from Sounds of Skyrim to Audio Overhaul?

I've been using Deadly Combat as my combat overhaul for the moment, but I've also looked at Duel as an alternative. I would like to ask those more experienced as to what their differences are, and any recommendations?

An alternative could be Lorkhans Vision.