In you opinion how strong is Arale canonically?

[Koitsukai]

I had the impression that Arale and the Dr. Slump universe are not actually the same as Dragonball's Earth, but they cross over sometimes. So Penguin Village and such was present when General Blue went there, but when Buu or Freeza destroyed the Earth it wasn't. It sort of occasionally shifts into the same dimension, if that makes any sense.

Like the island from Lost

[Meshack]

Another question: if Arale is really strong even by BDS standards, what canonical reason could there be for her not being chosen to participate in the ToP? It's a question that's not even supposed to be asked, I know, but if we do ask it.

One. Arale is a gag character. Two. Toriyama did not want Arale to appear in Dragon Ball again so he would not put her somewhere he does not want her. Yes they exist in the same universe but her power is not “real”.