Okay, I ran a playtest out a few turns to see how it went. Most of what I saw was good, the early game features worked. Indian raids were a very unpleasant surprise! I got into sloop vs. caravel and sloop vs. sloop combat with the AI, so that seems solid so far.
The first significant problem that I noticed, and verified with the Reveal Tile tool in worldbuilder, is that the AI did not appear to do any land scouting. I was picking off unvisited Indian villages and goodie huts well after turn 50, right outside their borders. I couldn't find a single scout for any of the AI players, seasoned or otherwise - just one Portuguese missionary roaming about. Their ships didn't seem to choose "Meet With Chief" either, as I saw Dutch ships enter villages and they remained tappable by my units later.
The second issue I noticed was some weirdness in AI trade. I sank Portugal's initial carrack with my first sloop. He built a sloop, but never did seem to do any more trading with Europe. His cities stagnated, and he never built a third, which suggests that he wasn't moving new colonists in from Europe either. Is it possible that the AI ship selection code is treating the sloop as a cargo vessel, and therefore not triggering either the purchase of new trade ships, or that the King giving you an emergency ship in exchange for a tax increase failed? France did wind up with two galleons, but after a late sinking of the original Dutch Fluyt by my sloop, I never did see another ship from them, either.