I assume Trotsky. Bukharin was more about strengthening the peasantry Through the NEP. Afterall the Left Opposition criticized the Right of that they weakened the Soviets and stenghtened peasants and Kulaks, setting the stage of introduction of capitalism. Trotsky (in 1936) would be about restoring the workers state (they called Stalin's USSR a degenerate workers state and state capitalist), ending buerecracy of Stalin and giving power back to the Soviets. In theory..
(Very very broadly speaking, also I am supporting neither so this is not out of ideological prefference, but what I think make sense with historical evidence. Also this is how I remember it, been a few years since I last studied Soviets interwar politics)
I think you are right about the "All Power to the Soviets" being a Trotskyist focus, you aren't quite right about a few other things.
Trotsky's term was a 'degenerated workers state', not a degenerate one, which would be a moral characterization rather than a socio-political one. He also did not believe that the Soviet Union was capitalist, state or otherwise. Quite the opposite. In his book
The Revolution Betrayed he actually praises the Soviet Union for having gone beyond capitalism, although he does not make a particularly good argument other than that stating that the rapid progress of Soviet industrialization would not have been possible in a capitalist society. Although why that would be he never makes a compelling argument, as far as I see it. Trotsky characterized it as a 'transitional form' that was between capitalism and socialism.
Trotsky fiercely argued against those who rejected that Soviet society was superior to capitalism, most vigorously after he had arrived in Mexico. There was a major schism in the American Trotskyist movement, the SWP over it. Max Schachtman proposed that the Soviet Union was a new kind of class society that he called bureaucratic collectivist. Trotsky vigorously argued against this, and later on, Schachtman started a schism in the SWP over the issue. Schachtman's 'bureaucratic collectivism' is seen as a fore-runnere to modern analysis of 'state capitalism', although that's not entirely accurate. There were those who saw the Soviet Union as capitalist from a very early point, but that was a small niche that included people like the founder of the Italian Communist Party, Amadeo Bordiga who called Stalin the "gravedigger of the revolution" to his face(who knows, maybe we'll see him in the Italy rework).
[A little bit of a tangent, but this was a funny exchange between Bordiga and Stalin]
Bordiga: With the aim of clarifying the question of perspectives I would like to know whether comrade Stalin thinks that the development of the Russian situation and of the internal problems of the Russian party are linked to the development of the international proletarian movement.
Stalin: This question has never been put to me. I would never have believed that a communist could put it to me. May God forgive you for having done it.
Bukharin and the Right Opposition definitely weren't very friendly to what you'd call democracy. Bukharin himself was a quintessential Stalinist. He was Stalin's close ally for most of the 1920's and was instrumental in the ban on factions and then the crushing of the Left Opposition. He himself was also the theoretical originator of some of the most infamous points of Stalinist political doctrine, including the well known 'Socialism in One Country' thing. It was Bukharin who invented that as a phrase, alongside some that may be lesser known to people who aren't students of Soviet history like 'socialist construction'.
A triumph of Bukharin and the Right Opposition probably wouldn't have led to a more politically liberal regime at all, just an economically more liberalized one. Some, like Bukharin's biographer Stephen Cohen, have speculated that Bukharin would have been something like a 1930's Deng Xiaoping, liberalizing the economy and paving the way for 'market socialism' like China today. Of course, it's all speculation at the end of the day, but I don't think such an outcome would have been too unlikely.