Honestly I'm still confused how Larian adding origin characters in any way detracts from playing a custom character? Other than the theoretical 'resources could be better spent elsewhere' I just don't get it. Having fleshed out companions (that could also double as a protagonist) in no way overshadows your custom character . . . that argument applies to any companion in any game regardless if they can be origin characters or not. Is it some feeling of loss that you are missing out on content by not playing the origin characters or something?
And I'm saying this a someone who has zero interest in playing the origin characters. I'll be playing custom characters and the NPCs will be my companions, done.

Some number of people apparently like origin characters . . . and Larian feels it is worthwhile . . . so good for them!