The 2017 black Friday sale had Gotha knights, warhounds and titans go out of stock, but all were back for 2018 sale, so I would guess cmon have every intention of continuing to produce models.
Rumors suggest that the 3rd book has all the content lined up, but no time to put it together and release it. Massive shame as I feel with a little advertising the game could do really well. The free ebook and YouTube videos got me into the game - a string of weekly battles on YouTube and a continuation of the storyline would do wonders for expanding the community. Keeping the blog/website up to date would be a great start!
I'd love to see a new army or two - I seem to remember the east of the world map has some potential to harbor another civilization. While the king was alive they could have been no threat at all, but with his death and the division of his kingdom they could creep back. I was thinking a largely inferior army with seige weapons and very poor magic (lacking in rank two units and no magic on defense chart).
An 'unseen evil' returning, or indeed the elementals of old would be interesting. A new list of motivations with a new army would be interesting too. I have to say the motivation system is my favourite part of the game, so leaving it as is isn't an issue if it means not breaking it.
Love to see new leaders for all armies, and all army subfractions brought up to three infantry choices. Also would be nice to see a bigger army size for friendly games with extra leaders added into the option choices along with specialists and infantry (take up three or four infantry ranks?). Patrol > skirmish > battle > seige? It would mostly be there for friendly games, since it's going to be too time consuming for tournaments.
It would also be nice to see Gotha knights and Gatekeepers on bigger bases. I guess this would require some rules tweaks, but currently the official models look silly on the bases they are supplied with.
Loads of scope for expanding, but skirmish games still seem the best and fairly endless in entertainment value as far as a single game could go. Having three armies with 24 odd ranks of infantry and 6 ranks of specialists gives you loads of flexibility for many many games. And waiting for those sales to pick up extras isn't much of an ask to expand way beyond the replay ability of a normal board game.