8 infantry: Purchasing 8 infantry is pretty useless for Russia’s second turn’s offense. Although infantry produced at Caucasus can potentially be of offensive use, it is usually far more useful to bulk infantry at West Russia. (If infantry are split between Caucasus and West Russia, Germany might decide to hit one of those relatively weak territories; if infantry is bulked at West Russia, Germany could take Caucasus, but would immediately lose it, and thus lose valuable forward placed German units). On the other hand, if Russia wants to trade or hold territory, infantry will be needed; those infantry have to be produced sometime, and the sooner they are produced, the sooner they can get to the German or Japanese fronts.
An explanation of why fighters are useful for trading territory: 2 Russian infantry and a tank could attack a German territory worth 2 IPC, held by 1 German infantry. The anticipated gain for Russia (assuming Germany doesn’t get a hit) would be 2 IPC (for holding the German territory), plus 3 IPC (the value of the German infantry), for a net gain of 5 IPC that turn. However, Germany’s counterattack would net Germany 11 IPC (because once the Russian units captured the German territory, the Russian units would have to stay in the territory, so Germany could destroy two infantry worth 3 IPC each and the tank worth 5 IPC). Of course, Germany would probably lose 3 IPC worth (because the defending Russian infantry and tanks would probably be able to take out at least one German infantry), but still, if Russia gains 5 IPC, loses 11 IPC, and gains 3 IPCs, Russia’s net value is loss of 3 IPC. Contrast if Russia instead attacked the territory with 2 infantry and a fighter; Russia would not have to commit the tank, so Russia’s net gain would be 2 IPC. Of course, these are not by any means precise figures, but it works out that fighters are often quite useful for trading territories. As fighters cannot land in newly captured territory, though, tanks are far better for capturing and holding territory.
1 fighter, 1 tank, 3 infantry. A third Russian fighter is useful for trading territories with Germany, without committing Russian tanks. Tanks are useful for threatening a number of territories, and for racing between the western and eastern fronts. Infantry, of course, are vital for any ground battle. This purchase has the advantage of being immediately threatening (the fighter can be used on Russia’s second turn to trade territory, to reinforce London, or to attack the German Mediterranean fleet, and the tank can be used to attack any number of German territories from either placement at Moscow or the Caucasus). This purchase, however, has the disadvantage of producing fewer infantry that can be used in subsequent turns.
3 tank, 3 infantry. Tanks at Moscow are useful for attacking any number of western territories on the turn following their production. 3 inf 1 tank at Caucasus and 2 tanks at Moscow can create a swift attack into Ukraine (or very possibly another territory) that Germany may not be able to straightforwardly counter, because of the numerous Russian tanks that will be able to defend.
2 tank 2 artillery 2 infantry. This is best suited for an early Russian contesting of Ukraine. With 2 inf 2 art produced at Caucasus, and 2 tanks at Moscow, Russia can make an early bid for control of the Ukraine. With the offensive punch of artillery in the Ukraine, Russia can try to force the Germans to route north , giving Russia valuable turns during which it holds the Ukraine and Germany does not.
1 tank 1 artillery 5 infantry. Much as for 2 tank 2 artillery 2 infantry, but this approach is more conservative, not threatening as strong of an initial gain, but able to hold better against early Axis aggression.
3 subs. Not generally recommended. This leaves the Russian player tremendously weak, not instantly, but around G3, as no Russian infantry reserves move up to replace losses. G1-G2 pure tank builds combined with industrial bombing can potentially spell big problems for Russia very early, as can a G1 transport build in the Baltic (because Germany can then invade London, and Russian fighters in the Caucasus are too far to do any good). Also, Germany can simply destroy the Russian subs with air at no risk, or could attack the Russian navy with the Mediterranean navy. However, if Germany does destroy the Russian subs, those are less targets that German air can attack on the critical first German turn (including the second UK battleship, the UK destroyer in the Mediterranean, and Anglo-Egypt), or it means less pressure on Anglo-Egypt (possibly allowing the UK destroyer at Anglo-Egypt to survive, or allowing UK to retain control of Anglo-Egypt, threatening an early Allied navy in the Med). If Germany does not destroy the Russian subs, the Allies control the Mediterranean (if Germany does attack Anglo-Egypt with the battleship and destroyer, the Russian counter of 3 subs 2 fighters probably means the early destruction of the German Med fleet; if Germany does not attack Anglo-Egypt with the battleship and destroyer but sails west to Gibraltar, unless there is an African bid, the Allies may retain control of Anglo-Egypt, and threaten an early UK Indian fleet into the Mediterranean. Of course, even if Germany does sail west to Gibraltar with its Med fleet, the German fleet is still in danger of a UK/US capture of Algeria, followed by Russian subs and fighters attacking the German battleship and transport off Gibraltar (with Russian fighters landing in Algeria) – but this leaves the Russian fighters very much out of position to be of any use, when they will probably be badly needed because of the lack of Russian infantry.
1 aircraft carrier / 1 transport. Not generally recommended. This again leaves the Russian player tremendously weak as previously described. This is another early bid for Allied control of the Mediterranean. Here, though, Russian fighters can fly off the carrier on R2, and be replaced by UK/US fighters, so there is not as much risk of Russian fighters having to be pulled out of position (Note, though, that as Germany goes immediately after Russia, if Russia decides to pull a Russian fighter off the Russian carrier, Germany can sink the Russian fleet at less cost). With this build, Russia has the bonus of being able to take control of a German-held Anglo-Egypt (with transported units from Caucasus and fighters attacking from the carrier), allowing UK to move its Indian fleet into the Mediterranean early. On the other hand, this navy is not really suited to threatening the German Mediterranean fleet.
In the next exciting episode, combat moves!