I appreciate how your team is able and willing to experiment with traditional ARPG trends and mechanics. I'd imagine being a new title and dev team gives you more freedom, since you're not making a D4, where players are either from D3 and expect GRift-like mechanics, or from D2, who expect actual itemization beyond "Damage on Tuesdays," or "green arrow = good."
LP, WW, and Item Factions have, so far, been extremely successful innovations, which I love to see. CoF in particular is amazing, because it's very empowering to SSF players, or people who aren't a fan of trading (me), but still allows for an AH to exist. I've quit a PoE league earlier than I wanted to before, simply due to not wanting to be assed with trading in that game, and am lacking in the skills to play with the SSF handicap. As powerful as CoF is, I'd imagine MG has a higher ceiling--and that's okay. CoF is powerful enough that I don't feel like I'm shooting myself in the foot by eschewing from the game's economy.
Another thing I love is how you managed to strike a balance between D4's loot system where only loot for your class drops the overwhelming majority of the time, and D2/PoE's wholly unbiased loot mechanics. I can still find stuff for other builds while playing my main, even though there's a significant bias toward my base class's loot for things such as helms, chests, and idols. The campaign fast-track for alts is also great, since it's only a skip as long as your alts are strong enough to fight way higher level content. My only complaint is this isn't carried through to Monoliths; alts should be able to skip the basic ones as well as fast-track some of the Corruption in Empowered Monoliths, so we can take on that harder content immediately if the alt is geared enough.