An AC purchase may save the Baltic Fleet for one round. 2 or 3 Rounds in a unification scenario. However, it does nothing for pulling the allies out of position to help Russia. If anything, it forces them to be as slow as they should be, so they are prepared to make a strong move against Germany.
However, an AC/2 Transports in the Med are very secure (considering you also have a BB/Trn to start with). It threatens/protects T-J, Egypt, IEA (if Canal is open), Madagascar (If Canal is open.), Kenya (if Canal is open); Gibraltar, W. Europe, S. Europe, Balkans, Libya, Algeria, Ukraine, Caucasus, Fr. W. Africa and Brazil all from the 4 sea zones in the Med. And you can bring a significant invasion force with you. (4 Infantry, 1 Artillery, 1 Armor w/BB shot and 2 Fighters.) Should you need to assault an allied position.
At worst it slows allied progression in Africa, givng you more assets longer.
At best it destroys allied progression in Africa, makes your southern fleet viable and prevents the allies from getting the Suez closed allowing Japan to float in and set up a 1/2 punch on allied shipping if need be. At least, it offers a method to platform 6 fighters (2 German, 4 Japanese) well in range of the E. Coast.
Dunno though. I don’t know if leaving Russia unmolested for the most part on G1/G2 for all those benefits is worth it. Not that the extra 2 Transports are that huge of a difference in price, considering the Baltic fleet dies on G2 with 1 AC, 2 Fig, 2 SS, 1 Trn, 1 DD anyway, which is much more expensive then the loss of 16 IPCs for 2 transports….