I personally have enjoyed playing my own characters, getting to know the existing Companions, and am now looking forward to being able to play as one of them and see their perspective on things. I feel that will make for a richer game experience as you can "get into their heads" and figure them out more. I particularly look forward to playing as Astarion and Lae'zel - who are both my favourite companions./quote]
I'd hesitate at saying you get to see the perspective of the Origins companions because technically speaking by playing as an Origins character you would be in control of them; my point being that you could play as Lae'zel and I assume, turn her into a 'Lawful Good' character through your actions (it would be strange if you could only pursue only 'evil' resolutions to any given situation with her), which some would argue would go against what we know of her character traits so far. The same could be said for Astarion.
It could be argued that you already see their perspectives very clearly by nature of them being companions and being quite forthright in their opinions and personalities.