but you cannot deny that he was on of its greatest exponents

While the revolution was a great propaganda victory for Socialists globally, almost every group that sprung up inspired by the revolution later became controlled by Moscow.

For example, the communists in my home country, the Communist Party of the USA, were summoned to Moscow by Stalin and had their more anarchist/democratic leaning factions purged, with some even being arrested and kept in Moscow till they died. The amount of control that Stalin and the Comintern had on international communism lead to repeated purges of more democratic/less Authoritarian socialists and basically ensured that Stalinist/Marxist Leninist Socialism was the only type allowed to flourish in any form for most of the cold war.

I certainly couldn't predict what would've changed had the Russian Revolution been more democratic/pluralist, or had a more democratic revolution inspired the last century of global Socialism, but I at least believe that Socialism wouldn't face the uphill "Gulags, Famine, Stalin, Mao" battle that it currently does.

Peace between us, war on the bourgeoisie, comrade

I would love nothing more than a united left, but it's more the actions of Marxist Leninist inspired governments after their revolutions, (Universal banning of non-Leninist Socialists, Universal banning of pluralist socialist democracy, Yugoslav's Split, 1956, and 1968) that makes me bash against ML's. It's hard to trust talk of leftist unity when the history of Leninism has involved the crushing of any other form of leftism since its inception.