Ah, ok, got you. Am a bit slow today (too many late nights this weekend)!
Here's some more info on OW. Let me know if anything's jumping out:
Pressing end turn does not enter overwatch by default. There's an overwatch button on the left panel (the one with reload). There a couple of reasons for this:
1) A player may not want to enter overwatch, but rather conserve AP for next turn. With AP bank and some toughness, it will be possible to carry several extra AP over
2) Will avoid the game accidentally mistaking a regular end turn with overwatch end turn, and displaying message (hey, you don't have enough AP). If you genuinely want to use overwatch, this message will be useful, rather than frustrating
3) Encourages players to think about what weapon, use mode they will overwatch with, rather than reflexively pressing end turn, and perhaps not having enough AP, ammo
On the flip side, there is the possibility of players reflexively ending the turn, instead of pressing overwatch button, but think reason 1) is enough to make separate buttons more attractive.
Currently tidying up the code for overwatch, then will add the threshold to fire, and AI overwatch. May restrict overwatch to certain enemies - seems like a good way to differentiate enemy types.