Gargantua; 6 tanks
Why? Because only with mobile forces that can move 2 you threaten the Germans or the italian mobile force. Units that only move 1 are too easy to trap and eliminate separately. If the threat is great enough, the Germans have to be conservative (put all their land pieces together). Italian fighters may therefore be more valuable against this play than normal play (because the ital fighters can land on and defend the German stack, should it be vulnerable to a tank strike.
Taamvan; 1 fighter, 9 infantry
Why? Because once you have 4 fighters (I add one using my DaveMod 3.0 = 2 to start, 1 bid, 1 bought) then Germany has to think twice about stratbombing your factories. The Germans can often bring the necessary escorting fighters, esp. once they have Leningrad. The worst part is that if they are able to bomb out your starting unit production, its better just to leave it broken then waste money repairing a factory they’ll simply take over. That may limit you to producing 10 or fewer units (if Moscow is bombed out)–many games I have like 25 income and max damage on R4-5 such that I must repair, but I’m only going to be able to build a few units. Build ##s early and quality later.
Another tip?
UK takes Persia turn 1.
UK factory turn 2
UK builds 1-2 infantry and fighters, which can fly direct. This is the only direct fighter pump and fighters that cannot reach moscow proper are usually destroyed as Moscow gets encircled.
Another tip?
Play with a bid, or with the Davemod 3.0 (see House Rules). Russia is too weak OOB, but it should still fall before G8-9 to make the late game fun.