I would be personally interested in seeing another ship for the escort, science vessel, and cruiser classes for the C-store. The new skins are good, however, I can think of three other types of ships for each class.
1) A ship that only allows 4 bridge officers instead of 5. Using the example of a science vessel, instead of having one lieutenant and one ensign for tactical (or engineering) there could only be one but brought to a lieutenant-commander level.
2) An alteration to this, as most STO players might opt for this new option over the previous one, could be only allowing 3 bridge officers, instead of 5. In this case, the bridge crew would be commander of science, and lieutenant-commander's in tactical and engineering.
Another thought I had was the captain rank. If we are an admiral, should we not have a captain below us? I realize not having a captain makes the issue of who really controls the ship, not at head...to some degree, but then even Ranker challenged an Admiral once. I think it might be nifty having a Captain level...that could really make things interesting... especially captain level skills.
3) The final idea would be based on all of the ideas above, one ship that has a bridge officer of each rank: Captain, commander, lieutenant-commander, lieutenant, and ensign. It would be up to the admiral to place the bridge officers into specific designations, of tactical, science, or engineering, with the one requirement of at least one officer in each of the three classes (science, tactical, and engineering).