LOL, you're right about the treaty elements! I must have been thinking about victory conditions or something
Oh, the boarding parties do double? I guess they're reasonable then - I thought they only went up to level 5 with 300 marines apiece.
The sensor issue I think is a balance thing - if the first few levels of sensors are Really Really Important and anyone who fails to know the secret that they have to research them is going to fall significantly behind, then it seems the sensor tech is unbalanced, much like Meson Blasters were in stock - Meson Blasters were the uber weapon and if you didn't know that they were and didn't research them, you fell significantly behind. (OK, it's not all THAT serious, given that it's only 2 levels of a tech, not an entire tech with 100 levels or whatever, so you can't fall TOO far behind - but it just seems unbalanced to me!) So it's a minor balance thing, but a balance thing nonetheless.