1. You most certainly need to bet the turn. Also bet more on all streets. I think a raise preflop is MILES better than a complete because CO posted and didn't limp. Against a limp I would prefer to complete.

2. You should be very happy to get your money in against CO.

3. I don't know why you think BB has such a tight range preflop. To me it looks like she could easily have 6c7c, Ac7c, 8c9c or even 54. If you really know she doesn't play those hands (deep & in position & probable 3 way pot with a fish), then of course fold.

If both players were unknown I would shove and be pretty happy about it.