So naval invasions are definitely in, I took Hispaniola from Spain as the British, and the Maratha Confederacy, apparently bored of owning all of India (I've been trying to get an army over there but haven't been able to yet due to now a second war with Spain and a war with France where I accidentally destroyed France), anyways, Maratha landed a small army of 500+ including howitzers there. I managed to kill 400 of them but my militia defence crumbled at the very end of the battle :/
Stupid Maratha has been nothing but a thorn in my side the entire game, previously attacking my trade fleets with it's magically gained fleets of European ships it really shouldn't know how to build.
I really really hate that militia units cost me over $450 each, as I hate having to break up my army for several turns in order to capture only a few regions. Or a cheap garrison unit would be nice.