I hope that with new book we will get:
4+ save on arcanauts or +1w
3+ save on thunderers and +1w
+1w to flying dwarfs
4+ save for gunhawlers and 3+save for behemoth ships
Overwatch ability for thunderers with drillbill
Command ship general option for behemoth ships
More battleline options (gunhawlers/frigates if you take command ship as your general, wardens/thunderers if you play as full KO, riggers if you take endrinmaster as your general)
More things that can be done by chemist, navigator, endrinmaster and admiral.
Better carbines and better mainguns for the ships
Gyrobomber "bombing run" ability
MW after charge with the ship
Each behemoth ship should be count as 10 model for the porpoise of scoring
Better countercharge mechanics.