Mark reflects on design highlights and lessons learned from 2021 in his annual address.
AFR apparently was very popular, but also way too polarizing.
Mark Rosewater basically admits not including Elminster in the set was a bad idea and that folks weren't satisfied with the flavour of the Tarraques mechanics
Flavour words are very popular, but they need to do a better job of making sure they aren't confused with Ability words like pack tactics.
MDFCs weren't as cohesive a mechanic between sets as Mark had hoped, but they were very popular (more so Kaldheim and Zendikar's especially then Strixhavens)
He also admits Kaldheim should have been 2 sets, which it should have been, it's an absolutely massive setting, especially compared to most MtG settings. I thought the D&D set should have been two sets as well.
Also the D&D set should have been more open to having previous fitting mechanics in the set like party (I disagree with this particular example for practical reasons), Adventures, and Level Up (I'd personally add Experience and Sagas and Historic as well IMHO.
since there will be no more Premier D&D MtG set set,and they aren't apart of Universes Beyond, my guess for their next apparance is a Commander Legends product where is the perfect sort of set to address complaints about AFR such as leaving Elminster and other beloved characters out, which D&D and FR alone has a ton of. I think this also means no D&D MtG merger in the future.