I agree to an extent. The Byakugan is superior to the 3-tomoe Sharingan but the only thing is that Ranmaru's dojutsu is superior to the Byakugan. I don't know how that is supposed to work since the Byakugan and Sharingan are derived from the Rinnegan, however Ranmaru's dojutsu is seen to have no connection with the Rinnegan. :dunno:
I personally think that it would've been awsome if the Byakugan somehow evolved into the Elder Son's dojutsu. That would be epic and bam! The Hyuga's might actually get lucky to surpass the Uchiha since Elder Son's Dojutsu >/= Eternal Mangekyo Sharingan.