-Yup, make there be Gaiden requirements that aren't losing units (including the Falchion thing with losing Tiki).
-Make Frey and Norne (I think her name is?) not Tutorial-only characters (give ability to recruit the two characters past the Tutorial)
-Release fucking book 2 (Heroes of Light and Shadow) INSIDE of Shadow Dragon, not the bullshit of "wah we didn't make enough money with Marth's game, guess the rest of the world didn't want book 2 then."
-Uh... Rebuild the final level, and make Medeus tougher, things like boosting his defenses and making the Divine Dragon not double the effectiveness against him.
I think there's more we can do, but it's not coming to me currently.