There are very few times where we will need a TBD. All of the Slot '42 sets should have the TBM since it went into service before we landed at Guadalcanal. Coral Sea and Midway are the only scenarios where a TBD would be needed, and neither are likely to happen anytime soon in the CT.
In addition, you have the problem with the F4F-3 which we dont have either, and it performed quite a bit better than the F4F-4 but only had 4 guns. Fleshing out the late war Japanese stuff, and something like the B-25/Betty bombers are more important IMO than a TBD.
Having said that, I think Arlo's Kate conversion looks great and will be a fine standin for the TBD if/when we need it.