The next new Kingdom (after Hellcrag) will be called “Vulpacea” and is expected to heavily feature Wargare Troops and/or include a Wargare-typed Hero Class.
Almost certainly not happening due to active Campaigns, sorry. Especially when a Campaign does something significant like debut a new Kingdom.
(edit) Certain content IS synced between Switch and other platforms, like the 6.2 update (Hoard Mimic) and special holiday events (Kris Krinkle).
There’s also the fringe benefit that sometimes content that launched bugged on PC debuts fixed on Switch (e.g. Burning Ocularen released as – IIRC – Yellow/Brown making it incompatible with its own Faction, but launched on Switch with the fixed colors, Green/Yellow).
Maybe you’ve noticed how the cpu occasionally misses matching 4 or more gems? I suspect this was a change to the AI some time ago. Agreed that certain troops (e.g. Aziris) are almost completely useless in the hands of a cpu because of how much their utility depends on board layout, but I don’t see a need to fix this. For example, when running Clockwork Sphinx (which I do like 80% of the time) I don’t always pick an ideal Mana Color for my team – sometimes I’ll pick an off color when it will yield a match of 4 or more Gems, or simply to deny the cpu access to that color for a turn.