Firstly, I don't think that the late CCCP is the best comparison. In 1989, the Union was "the man"--those pushing for more radical change wouldn't be satisfied with it, and those pushing for less radical change, well, the center could not hold. This will also be true in the '20s--but here, the Union is the new thing, thus, that radicalism will quite possibly strengthen rather than weaken it.
Secondly, even if you don't go from dictator to democracy immediately, that doesn't mean that some form of democracy isn't a good end goal. Lenin holding power for ~10 years and then laying it down for reason of ill health is a great point from which to arrive at a very genuine democracy 20, 30 years down the line, especially given how much positive impact the other reforms you mentioned will have in the interim--public confidence in the government will be at a very high point if people more moderate, intelligent, and tactful than Stalin are in control and don't push the envelope on collectivization whilst keeping other positive reforms.
I would likely offer minor incentives to collectivize from the bottom up--it's easier to get people to work with their trusted next-door-neighbor in many cases--and even then not collectivize completely (at least in practice) but rather declare that your surplus output is split into 3 portions--one for you to spend at your discretion, one that goes to the state as tax, and one that goes to a communal fund for social insurance and communal projects. Thus, people become more adapted to a collective mindset whilst still having an incentive to improve their land, and can't egregiously hide food etc. without cheating their neighbors--and small-group shaming and social consequences are much more effective punishments than the long hand of the law. Likewise, allow for small scale markets and even a few factories within an NEP-like system. This process, though it will not produce as much short term revenue for industrialization, will be much more sustainable, and furthermore with a more functioning Soviet democracy people like Sokolnikov who actually know what they're doing can prevent things from getting to the point in 1933 where Stalin felt that he had to export massive quantities of grain to keep the Rouble in control, to the point where the 1933 famines and Holodomor happened. The Great Depression will be bad enough overall that if the Soviets can avoid the worst of the troubles they can still look like a very attractive place for investment; I would pass laws saying that factories built by foreign investors formally belong to the state but are leased indefinitely to said investors. These investors must pay off the cost of land, labor, resources with a portion of output but from there keep generous portions of their profit. With confidence in the legal system and a Soviet state that can offer the proper incentives this will look very attractive during the height of the Depression. Using the proceeds and/or tax revenue, the Soviets can from there build many more state-owned factories, and Soviet democracy enables experimentation with collectives. Meanwhile, labor protections and state-backed unions will let the Reds save face--indeed, proving to the capitalists that they could still function in the socialist system can be justified as a foreign PR move.
So, overall, with better management the Soviets should be able to industrialize nearly as much as IOTL, whilst building much more public confidence and achieving an even higher standard of living.
And then the Nazis invade. But this time, the Soviets aren't fool enough to trust them, and Commissar of Military and Naval Affairs Lev Trotsky and Marshal of the Soviet Union Mikhail Tukhachevsky are ready to cast them back to the hell from whence they came. The unpurged Red Army is a brutally effective fighting machine, and the Soviet people--much more confident than IOTL in their government--back the Army to the hilt. By 1944, the Red Army is on the Rhine, having singlehandedly liberated Eastern and Central Europe from German Tyranny. Soon afterwards, having seen the people's loyalty, much more political reform is introduced, further fulfilling the promises of Soviet Democracy...
(or so the propaganda would claim)