I like the kedging idea, especially once land is introduced in battle instances, as it will be a genuinely helpful means of pulling a larger ship off the shallows, or even the opposite, setting up a larger SOL as a battery, and preventing an either-side-of-the-line situation like Abukir Bay.
I also rather like the reinforce idea, especially to help ships close to the epicentre of an explosion, as that tends to devastate crews.
However, while the main parts of the game are still being worked on, I'd personally prefer this to be a fairly low priority option, the animations are already a little off in battle, and I doubt an unanimated pixie-powered longboat toddling about would add much to current immersion.
One other thing to bear in mind in regards to seeing the longboats is that there is a considerably smaller amount of seaborne debris in game than in the real world; in PvE it wouldn't be too hard to implement, just give a low 'visibility' value for the AI to play with, but in PvP it would be a death sentence for the troops involved, especially as the low mass and armour of a longboat would make it a nice painless ramming target for careless players, and an easy kill for those more attentive.