I took it to just be Toyotaro/AT poking fun at SSJ2 being the least distinct of the forms visually. They did a similar thing by poking fun at SSJB having a shitty original name and also called SSJG "SSJ Red"
With Goku I'd say regular SSJ is his signature due to him using it the most, plus he stopped using SSJ3 in Super for the most part and Blue is just a recolor of it. He still hasn't used UI long enough for it to be his signature form. In GT SSJ4 is definitely his signature form though.
Gohan's...
But SSJ3 is most likely the greater boost of the two when you consider that Gotenks does not even consider SSJ2 to be worth using before jumping to 3. However that could just be Toriyama hurrying it up and getting Gotenks into his final form by skipping the middle one similar to Gogeta not...
2x is more appropriate for the jump from Grade 2 to Grade 3. SSJ2 being 2x makes it retarded that Gohan even lasted half a second against Cell in the beam struggle after losing most of his Ki to his death beam.
It's only small if you're trying to have it run parallel with Gotenks' Fusion Dance SSJ boost and trying not to godnerf the latter. 4x is plenty enough for the feats SSJ3 has