To answer the points about input sources for abstracts, Beyond has a few ways of generating abstracts, more traditional ways with banks and oscillators, and other methods such as synth images which can take pretty much anything in Beyond as an input cue. From what I've seen (as a Beyond user, and observer of Swami) it's a different way of achieving the same things between the 2 softwares. As was discussed some time ago, I think the fact that we have Swami doing some amazing things with LSX, it is seen as an indication that Beyond is less capable. I think it's more a case that we haven't seen a talent like Swami using Beyond.
I spent some time replicating some similar effects in Beyond and found them possible. I'm sure with enough time and familiarity (and talent!) you could produce equally good work.
I say don't get hung up on the tool, worry more about your commitment to the task. As Swami says, none of the programs have an 'I win' button for content.