The Buu saga actually has moments that put the Base Saiyans above Frieza.
1. They agree not to use SSJ at the tournament, yet nobody is even concerned about fighting Piccolo and #18. Vegeta even quotes he'll still win and nobody comments on this, nor does anyone say its a unfair advantage for Piccolo, making it clear all Saiyans believe they can at least put up a fight in Base.
2. Dabura is ordered to eliminate all but the strongest 3 and Kaioshin, the 3 Saiyans are left standing. Later its shown they knew nothing of the SSJ form, so that power couldn't have been taken into consideration. The only question is if he sensed their power before arriving or after (meaning before or after they starting suppressing, if after, then this point is meaningless)
3. Kaioshin stated he was 1,000 times more powerful than Frieza and yet he was scared of Goku in his Super Saiyan form which is only a 50 times multiplier from his base power.
1. You actually right, i forgot about this, Piccolo (after the fusion with Kami) was at the same level of Android 17, that was stronger than Mirai Trunks SSJ that was stronger than Frieza 100%.
3. Actually somebody said that 1000 times quote was only in the Anime, but still there is the fact that the Supreme Kai said that all the Kaioshin were able to kill Freezer in one blow.