I personally don't see the Soviet faction dominating, given the technocratic characteristics. The Domestic faction by itself had enough members to dominate the country, so without a central figure in the Manchurian faction we would see the Domestic ruling with the Soviet as partners, and the eventual takeover of the military from the Manchurian and Yanan. Of course, this is the conventional view, since we don't know how things might have gone.
Hmm, probably right. Though one of the main reasons the Soviets supported Kim IOTL was they didn't trust the domestic communists due to their early Comintern links. Lacking a candidate with Kim's perfect set of characteristics (in Soviet eyes at the time), I wonder who they'd go with.
Lacking Kim means that the returning Yanan group fighters may not be disarmed as they cross over from China as happened in OTL. That might lead to them remaining a serious power group within the military.
If Pak Hon-yong is all "Yeah bra the people in the South will totally rise up in support of us" like in OTL, and the Korean war happens in a somewhat similar way, then the Yanan faction might have an advantage. They can blame the domestic communists for the failure of the South to rise up, and remove them like Kim did OTL. If the Chinese intervened as OTL, then the Yanan group might be able to use their presence to back a power grab of their own. That would see a China-aligned DPRK during the 50s and 60s, which might have interesting effects.