Now indra the dracula of sharingan,how powerfull could this guy be if he could switch MS designs on the go but gets a small 5 second cool-down??.....Now when you think Dracula, you think of the One,The First and the Originator who gets all abilities of all that came from his blood..Now think about how random MS abilities are Eg: KA/KamuiI/Ama..If you think about if all these abilities have one connection that they share when the user has DMS and thats "Susano'o"..Now wat if all these random MS abilities had a source,a original Database that was the Originator of all random abilities of the MS thats stored in all uchiha's genes/blood which mutates when the uchiha gets MS nd gives the MS user a abillity that was rooted into there blood from birth?..Ok now all uchiha's who had DMS potentially had susano'o,Obito said it was rare but he himself had it,So what if Indra had all these stored in his blood? woul he need rinegan?
At bold,even if your speculation is true
But
He still lose to Ashura, you point?
But you must know, if you believe in god even god of NV, you surely can't put aside/ignore the fact that god able to give it creations some unique power that not related to any blood line.
And also the person that other than Obito that having dimensional base S/T tech and not wormhole base S/T tech is Kaguya and he is closet to the GOD of NV in power.
And other point if you take Hago statement literally, he said that kamui is GOD authority power, That mean I don't think Indra is so special that GOD like him or trust him.
KA also I'm doubt it, it relation to Kaguya sharigan power never been found and I assume that also is unique power that given by GOD of NV not a bloodline.
But other tech is plausible like Ama