Well Peter, if you actually took the time to make it better, instead of releasing what, to me, felt like a half finished game. In my opinion, Fable 2 is the better game. The touch system wasn't as great as what it was hyped up to be, i preferred the expression wheel (Fable 2) instead of being given a single-choice of 3 or 4 different expressions a turn (Fable 3). The game was too story driven, and of course, not enough to cover the main aim of the game, being king. I felt forced to do the story, unlike Fable 2 where the story felt optional for the majority of the game. Another thing i felt was Fable 2 Albion felt much much bigger to what Fable 3 Albion did. I think the way there never seemed to be a countryside sort of area between towns was what disappointed me the most, (slightly more than the other 2 complaints), the lack of the need to explore the world.
For Fable 4, they need to really go back to Fable 2 and have a look, take all the good from it, same with 3 (such as the combat, combine them, and chuck a few great extras to make Fable 4 the stand-out game from the series.
They released Fable 3 far too early, and far too soon after Fable 2 for any great deal of change to be made. So if i were Peter, i would focus on making a breath-taking game (one he might actually keep his promises in), take as much time as required to get things up to standard, so you don't end up saying 6 odd months down the line that it wasn't what he wanted or up to his standard
(I never played Fable 1, so i wouldn't know anything about it)