Solasta's' DLC's maps have actually grown on me the further I went, and I was pleasantly surprised considering the same people designed the freaking Lava Forest and overuse the "push the block, knock down a trunk" interaction way too much. The non-linearity in discovering some late-game areas is really neat, although there are quite a few scripting bugs (I basically can't continue a certain questline if I want to get the resolution I want because doing so instantly makes my reputation with one of the factions negative, potentially because I went to a certain area before I got the quests for it, but it's kinda stupid they don't account for it by checking whether or not you already did the relevant quest, and in an earlier quest I negotiated the alliance between the two, so it's even dumber).
Still...
The swamp and the magic research complex are both genuinely great locations with some nice fights, actually rewarding exploration, and good-to-great map design with many routes and approaches to encounters. It's an enormous step up from how the original campaign was.
...Anyway, while the writing is still god-awful and the raw 5e combat still feels very rigid to me (though it might be because Solasta has very bad AI which would just focus a reckless raging barbarian while there are undefended spellcasters with low AC, and very few weapon types/additional things like potions and throwables), Lost Valley is actually really neat. It could do with fewer bugs in the quest chains, though - it really feels like they got confused in their own net of triggers and conditions and the result works well only if you carefully follow the plotlines without hopping too far ahead if you got a lead to some late-game place early.
