One of the biggest things I'm looking forward to in WH3 is the updated Chaos factions, because good lord Chaos in its current state might be one of the most boring campaigns I've played in any TW game to date. I've tried all the mods I could find that mad significant changes, I've tried all different difficulties and unit sizes to try and make it fun in any way, but it just isn't. It's slow, it's unexciting, the units and lords are almost totally uninspiring. Early game armies are boring, late game hellstacks are too easy to win with. The "tech tree" is more of a tech shrub, the starting position loses its luster after like ten turns, I could go on. I'm lumping in Beastmen here too for the most part, but at least there's something satisfying about the braying Beastmen herds. There's none of that interest for the Chaos faction.
Since I just spent a whole paragraph kvetching, I guess I'll add some stuff I like. There are some genuinely good mods for Chaos, even if a lot of the units are crippled by GW/CA asset protection. I remember the old Chaos Undivided mod, and I think the most recent one I played with was Total Chaos or something along those lines, and both are amazing at doing what they can with what CA gave them. Even some of the simple reskins (i'm thinking the ones that skin Chaos to look like they all follow one of the Chaos Gods) make it marginally more fun. So props to the modding community for making one of the most bland TW campaigns in the last few games playable.
CA had such fantastic lore to work with and this is what we got. Also, I know I'm like three or four years late to complain about a Game 1 faction but it's just unbelievably boring.