As for SSj with the god flame, it's only a transitional state, it's just SSj put over a fledgling SBG. Also, Goku was able to briefly stop Beerus in his base form, and going Super Saiyan didn't noticeably help him, it was probably done just for flashiness or to give Goku a sense of feeling that he was giving it his all (he didn't go SSj2 or 3 at that point either, which indicates they wouldn't have altered the outcome). It's probably best to see the power retained from SSj God as a flat increment rather than a multiplier. That level is so high that Goku's previous power is a mere fraction, be it base or Super Saiyan, that's why I don't think there is any difference between it and SBG.
So at that point Goku basically had most if not all the power of SSj God, but no mastery over his ki required to put Super Saiyan on top of that in a viable fashion. If he went SSj, it would all be the same, as he'd just multiply his natural ki, not the one he got from SSj God. That's where Toriyama's remark about it being the most beneficial to train his base and SSj forms comes in - the result was full mastery over the god portion of his power, and the ability to go SSj Blue. At that point he could also suppress himself to just the natural portion of his ki, and put regular SSj, SSj2 and SSj3 multipliers on top of it, thus creating the two bases. "SSj with the crimson fire" had long ceased to exist by that point. That's how I see it at least.
Also, in addition to what you said, the way I portrayed the Grade forms can be seen as controversial

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