Who wins? Golukky (Goku/Luffy)? Naroku (Goku/Naruto)? Ichigoku (Goku/Ichigo)? One of the fusions which doesn't include Goku somehow?
All fusions have the combined power sets of their forms (i.e. power level, chi, etc. are all interchangeable to the users) and similarly combined mindset.
Scenario B- Who does the best out of the non-Goku fusions?
Naroku has the most power of everyone present. That and he is in Super Saiyan. I pick him.
And in Scenario B, it is definitely the fusion of Naruto and Luffy. Luffy is, as far as I know, the statistically strongest character from a purely physical standpoint, and if you combine that with Naruto's ability to create clones and think creatively, with Kurama's extra power for assistance, and I really can't see Nuffy(or Lurato) losing.
They can all go super saiyan. I'd figure raw power would be pretty even between the three Gokus- the others may add a little, but not much compared to the whole.
And Golukky does have Haki and Stretchiness. Ichigoku, sword and hollow regen in vizard mode.
Luffy adds far more to Goku than any of the others.
The only thing Naruto adds to Goku that he did not already possess is a healing factor, and Ichigo adds nothing I can think of to Goku. The increase in power level would be completely inconsequential.
Luffy adds precog, the ability to further enhance his physical strength and defense, and most importantly, virtual immunity to blunt force attacks and stretching. See, the thing is, Ichigo and Naruto's amps are linear, they add to his strength. But Haki and Gears multiplies Goku's already incredible power.
"The Daemon lied with every breath. It could not help itself but to deceive and dismay, to riddle and ruin. The more we conversed, the closer I drew to one singularly ineluctable fact: I would gain no wisdom here."
Ichigo has healing factor... but I think you're forgetting some of Naruto's abilities.
Like chakra arms, which he can make at will. Clones that operate near his full strength if he puts enough chakra in them (and he uses as decoys, unlike multi-form. Imagine the advantage in a DBZ fight of someone using up much of their power blowing up a fake). Superior sensory abilities. Henge.
For starters, Naruto's "power level" as it were is going to be above Luffy's. This will put the Naruto form above the Luffy form as we all know power levels are the only thing that matters.
No but seriously, Sage Mode and Kyuubi Mode both have abilities similar to that of Mantra and stat enhancements. The only thing worth noting there is immunity to blunt force trauma, which is nothing new for Goku to fight(see Buu). This fight will have ki blasts, which will nullify whatever advantages Luffy might give Goku.
Meanwhile, Naruto has two thousand clones that all, technically, have a higher power level. And the strongest technique here: the substitution jutsu.
naruto's sensory ability is pretty even with Luffy's precog. Also, chakra shrouds and nature energy frog kata are very similar to haki. Haki to me seems very similar to chakra shoruds in Naruto.
The immunity to blunt force matters very little when naruto has attacks that cut at the molecular level. His gear third with size manipulation would make his attacks hard to dodge though. naruto can also strech in a sense with his chakra arms.