Assuming we aren't going to get any other models, which seems pretty likely, A few things I'd like to see would be;
Larger Garrison capacity for Frigates (11 to 12 so we can run a hero in the ship with a Ark Company without it being slowed down)
Some sort of ability for Ark Company to disembark and charge after a Skyvessel has moved/flown high
An extra bit of rend on some of our guns would be nice.
As mentioned, Monstrous(Ramming) actions for our Skyvessels.
Some sort of streamlining special weapons (I'd love to be able to run a squad of Ark Company with 3 Skypikes in 10. Thunders with 4 Aethercannons etc.) But that is very much wishful thinking and wouldn't really work with how the actual kits are setup