So basically, what if the farms were never collectivized?
</p>This one is pretty easy to answer. No Soviet collectivization means Nazi Eurasia from Brest to Yenisei River and from Norway to Persian Gulf. You see, the short-term effect of collectivization was to rob Paul (agriculture) to pay Peter (industrialization) IOTL, and there's absolutely no other source Soviets could draw from. Nada, zip, zilch, zero. No access to world credit market, no markets for Soviet industrial goods to pay for industrialization with contracts to supply industrial products in the future (the way Czarist Russia paid to US companies in 1914-1917 to build small arms factories to produce rifles for Imperial Army), no capital reserves, no export items but raw products. So, by taking collectivization out you pretty much make industrialization an non-starter.
What would "no industrialization" mean for USSR, in military terms. Quite a lot, as you would imagine. Just forget about all those trucks, T-26s, T-28s, BTs, SBs and fighter planes of IOTL. Not gonna happen. Nowhere to produce, no raw materials to produce from (you don't exactly mine iron and aluminium, you smelt it out of ore), no workforce to make the stuff. Polish 1939 army would give you a pretty good idea of "deindustrialized" Red Army. A single tank battallion per an army, with "tanks" being mostly MS-1s (Soviet derivative of FT-17), plus couple of elite regiments on allmighty Vickers 6 ton. What's probably even more important, precious few of those who went through compulsory army training in 1933-1941 (IOTL having a somewhat decent exposure to tanks, trucks and planes) would be familiar with any equipment of post-WWI vintage IOTL. So, no reserves of men in their best fighting age (25-35) being familiar with motorized equipment.Now, let's ask ourselves, would absense of Soviet industrialization prevent Hitler from coming to power? The answer would be "Nope". Nazi weren't allow to became a leading German political force because elites feared Red Invasion. Hitler had been enabled as a tool to prevent the Red Rot, lefts coming to power from within due to internal discontent, through ballot box, militancy or combination thereof. So, industrialization or no industrialization, just by virtue of being there, USSR would inspire far lefts all over the world, Europe included. And that makes Germany-1933 inevitable.
What would change between 1933 and 1940? Not that much, really. Spanish Civil War would start as ot did IOTL, but Franco's victory would be faster (war, without T-26s and I-15s, would end sometimes late 1937-early 1938). In absense of credible Soviet military threat to Poland (more on it later), British and French would be even more inclined to sell Czechs (IOTL they at least had a chance to help Czechs by co-operating with Stalin, ITTL Stalin would not be in a position to do anything about the events) and give Poles guarantees. So, 1938 and 1939 would go as ITTL, with Czechoslovakia eaten alive and Poland spectacularly defeated.
Now, stuff starts to get really interesting. Let us be charitable to Western part of European landmass and assume that Hitler, being a good anticommunist, ignores Alsace question and goes after USSR in summer 1940, instead of France. This is quite likely, actually, as semi-peasant USSR makes extremely tempting target. What resistance would Red Army be able to offer? As I said, I don't count on it being better than IOTL Poles. Pre-industrialization, Poland was considered at least as credible military power as USSR. Soviets spent 15 years (1921-1936) and untold amount of resources, building much-talked-about Stalin Line to defend itself against potential attack of much-feared Polish army. So, there's no reason to assume that Red Army would do any better in 1940 or 1941 then Poles did in 1939. Nothing happened ITTL to boost it's fighting power the way industrialization did IOTL. So, you can assume frontline along somewhere East of Volga to the end of 1st summer of war, and somewhat West of Yenisei by the middle of 2nd year (Nazis, unaware of Big Oil of Tyumen, wouldn't take Siberia, the decision they will come to regret later). Now, how many of you, my readers, do actually believe that "Great Nazi Reich from Yenisei to Rhine" would actually spare France and Benelux with Scandinavia for long? So, whatever you do, you have Nazi-dominated continental Europe and Near East by the end of 1942. Now, taking into account that Nuke would not arrive before it did IOTL, Hitler has 3 years and industrial and resource capacity of half of the world to terror Britain into signing of peace agreement along the lines of OTL "brotherhood agreements" between USSR and it's Eastern European client regimes, with Brits being not allowed to let American bomber deployment (I'm being very modest by not talking about Unmentionnable Sea Mammal, which looks more realistic ITTL, but is not really needed). With FDR dead as per OTL, you can be pretty much sure that Nazi-American peace agreement along the lines "what's yours is yours, what's ours is ours" would be signed before X-mas of 1945.
So, you wanted to talk about Russian farming ITTL? Well, options are limitless. We can talk about positive effect of Jewish and Slavic corpses would have on soil's fertility. We can count on at least couple of million Soviet Jews and several times that of Russians, Ukraininas and Belorussians being killed (see Generalplan Ost for more details). Alternatively, we can discuss permafrost fertility in Yakutia or around Magadan... (Sorry for sounding so "horror movie"-ish in this "agricultural" paragraph, but I'm telling truth, whole truth and nothing but truth, as far as Nazi plans are concerned).