Yes, when the implication for Freeza > base lied heavily on Super, you feats and many others ignored it and wrote it off as contradicting the original manga... because the manga, and I agree in it, tells a different story. So why act the oppposite now that you have found a piece of evidence that favors your base > Piccolo side? That's just using Super when it's convenient. I got and agreed mostly with ppl who used this on the neo thread because it toally evened out the earlier part of Super who laid out Freeza > base Goku... which showed Super wasn't even consistent on this. So it's better to keep the debate to the original manga. Super is a mess in terms of power scaling, AT isn't the same in regards to his thought process and RoF came with a pile of inconsistencies.
Looking at the manga alone, I can see evidences that can imply both scenarios. However, I see the Piccolo >>> base Saiyans as standing out, in my interpretation of the story at least.
Post RoSaT, we know Piccolo reached a new level. When Goku stated, confirming Piccolo's suspicions that he was indeed useless vs Cell, Trunks reacted surprised... and that Cell was already strong enough, as far as Trunks knew, to heavily outclass Super Vegeta. So Piccolo should be at least relevant to that Cell. We know from Vegeta's confidence, that heading to the CGs, he likely surpassed 50% Goku... tho the gap between them was still vast when Goku reached FP. Piccolo isn't on Vegeta's and Trunks' level as Cell gives emphasis to those two Saiyans separately. However, he wasn't put down by enemies who were slightly stronger than Vegeta. He was standing there, bleeding, but without serious injuries. We have already seen what gaps such as 1.5x like Goku vs Ginyus can entail, 2, 3 shots already cripples the opponent. The Juniors couldn't do that to Piccolo. Piccolo wasn't putting up the same kind of fight Vegeta and Trunks were, but he was still standing without serious injuries, with no evidence, none at all, they held back on him. The point of the Cell Juniors was to make Gohan suffer. They held back not to kill the humans because they wanted to see Gohan suffering for him to snap. There's no sense in holding back vs Piccolo to the point Piccolo wasn't in a damgerous position if they could put Piccolo at risk quickly and add to Gohan's suffering. That knocks the whole point Cell made them down. So if Vegeta is like 60% of Goku (he surpassed 50% but was still in disbelief at Goku's 100%), Piccolo can very well be at 50% Goku's power... which also matches Trunks's face of surprise upon Goku saying Piccolo was useless. Trunks didn't think of the power Goku showed at Karin as useless yet, so it all matches up. Goku stated he likely wouldn't have a chance, but he didn't regard such power as straight up hogwash vs Cell. That's the 1st indication Trunks gets, from Goku saying Piccolo was useless, that power of that calliber was useless vs Cell, which matches up with Piccolo being at 50% Goku's level and may raise awareness on Trunks that Goku is still likely holding back power compared to what he showed at Karin... and also possibly indicates to Trunks, that the level Cell showed to him and Vegeta was just the tip of the iceberg.
As for the Boo saga, the implications from Babidi regarding everyone but the Saiyans as trash is kinda weak. Because they were all suppressed down to 0. Babidi couldn't sense them so he obviously used some kind of magic to gauge who was useful and who was not. Guess what, their level of usefulness came down entirely to their abilities in filling Boo's energy 100%... which they couldn't do as base, since SSJ2 Gohan only filled half. So Babidi likely only got the info that three of them could fill the 100% but had no clue at all, as to how that translated to their strength, hence why he kept being surprised.
The other point is a strong one, I admit. But also has its flaws. What if Gohan thinks his base is weaker than Piccolo and still proposes the rule? Does he think Piccolo will KO him knowing Piccolo knows Gohan's intentions behind hiding his FP? What merit does Gohan think Piccolo would earn in winning against ppl Piccolo knows handicapped themselves for a purpose and that could kick his ass otherwise? That goes more in depth on Gohan's understanding of Piccolo. Plus, even were not that the case, Goku used SSJ2 in a pit, quick burst. Nothing stops Vegeta, for instance, going SSJ in a burst, in a camera flash light and KO'ing Piccolo, so quick the yellow hair wouldn't be perceived. They wouldn't break the rules, because the rules weren't there to make it fair for the non-Saiyans... it was there to protect their identities. And that's it.
Furthermore, kid Trunks can't tank #18, has to dodge from her blast and needed to go SSJ to fire a blast moderately above her in their Budokai match. So at least, his base is on her level... at most slightly above. But the base kids are on 18's level... who is hugely outclassed by Piccolo. We saw that Goten was giving a hard time to Gohan in their sparring. Gohan even had to fly. When they both became SSJs, Gohan was still sparring intensively with Goten, sweating to defend from Goten's kicks. So Trunks and Goten aren't far below Gohan. The Daizenshuu comes as far as to put them as equals under same states, however I think that's exaggerating it, but Goten is close to an extent. So Gohan couldn't be THAT much above 18 in base. He could be fit perfectly into 17's level... who Piccolo was equal to before rising to a completely new level in the RoSaT... showing the base Saiyans, base Gohan more specifically wasn't near him, unless you either ignore the sparring sessions and say the kids are wayyy behind Gohan or assume the kids and the adults have different SSJ multipliers, which is, again, assuming things.
So yeah, I'm way more comfortable in the Piccolo >>> base Saiyans side and base Goku being on 16's level more or less.
As for Kaioshin, he was frightened in the spaceship. He wasn't the same, he always wanted to take the safe route. He wasn't think rationally. He saw and sensed Gohan, saw how difficulty was to paralyse him... that was SSJ2 Gohan... and yet he panicked at base Vegeta's powers... even if he forgot about sensing Gohan, that much shows he is showing way more abrazive reactions at way lower powers than ones he was more collected before. So he is in a different vibe at the spaceship, likely because:
1 -- he's overestimating Babidi's minions, so he sees everything from the Saiyans as impressive
2 -- he is surprised that not even transforming, Vegeta could already do that
3 -- Toriyama messed up his characterization and changed how strong he was supposed to be
But when he battled Boo, the strong aspect of him seemed to come back, as he can move Boo back, even if slightly, survive multiple hits, when Boo was already >> SSJ2 Goku there, and use his magic power to explode the blast who was sending Gohan flying. The strong and Godly aspect of him seemed to have come back then... which leads me to think all his reaction in the spaceship came from cautiousness, PTSD, weakeness of character in face of his fear of Boo, and trying to be as weary as possible when he knew the threat Boo posed, which none of the Saiyans knew.
So Kaioshin, being said by Piccolo as above him, can still easily be above the base Saiyans and have all those reactions due to a momentary weakness in face of the fear and cautious approach he wanted fearing the terror of Boo.