An easy solution to a few things:
Make Venice a DLC, and make it possible to disable the DLC. This way, if they are the alleged 'hard-to-master' civ that a couple of folks have conjectured, then you can:
- 1) Opt in to having them at all.
- 2) Turn them off whenever you aren't the one playing them, thus making the AI incapable of failing as them.
This would work for any civ that is 'pro' or whatever, in terms of being powerful but in need of complex strategies.
As to whether Venice actually is or isn't a 'pro' civ -- or will even be included at all-- I don't know. Since we know Portugal and Poland are already in, I'm not so certain we will be seeing any more European civs. With 3-4 civs left to fill (depending on if Morocco is in or not), and with already 2 civs from Europe and none thus far from Asia, I would think the last 3-4 civs might be Asian, with one last civ coming maybe from North America, South America, or Africa rather than Europe.
edit: For purposes of grouping civs, I count Assyria as 'Ancient' (along with Rome, Greece, Babylon, Persia, and a couple of others). We could also see one more 'Ancient' civ, too.