it just seems to me that it would be a cool fight bc i am certain that luke is way more powerful than krayt bc he was fighting abeloth and krayt at times during their fight. we also know that sidious is way more powerful than krayt as well and the popular vote is that the son is more powerful than sidious, i agree with this as well.
so in the end it would be 2 very powerful darksiders vs aan extremely powerful darkside entity. now i do agree that abeloth would win in the end, i do not agree however that it would be a curbstomp.
The problem with the team is that it takes Light AND Dark Side to take Abeloth out. The team in this case, while ostensibly more powerful then Luke+Krayt+Ben+Vestara, doesn't have access to the light side, and so must lose.
Son+Luke, on the other hand...Son is more then adequate compensation for Krayt and Vestara.