No. Really. Given everything we know about Tevinter, the Magisters, and Magic what you're proposing is about as realistic as complete mage-templar harmony. Unfettered magical research will almost invariably get around to 'new and interesting' applications for blood magic.
I really hate to even coming close the Law of Godwin but in this case it's actually an apt comparison. Unfettered magical research will almost invariably lead to some serious Mengelesk sh!t going on, given the only real viable path left for it is blood magic and most people aren't likely to volunteer for that sh!t.
Or are we all just being naive and assuming that after thousands of years of studying magic everyone involved just failed to somehow notice the uber-powerful field of carebear magic they could study?
Well hold on there... first off, I'm not the one who proposed "unfettered" magical research... I'm only in favor of less restriction than what the White Chantry Circles allow, not unlimited freedom. I also said that I don't agree with everything about Tevinter culture... mainly that includes the oppressive or immoral aspects. The thing is, even with all of those negatives, it's still a lot better for a mage to be born there than most other places in Thedas. Rivain and possibly Nevarra would be decent options as well... although I have a strong distaste for the Rivaini seers and the overall refusal to properly contain and prevent abominations in that nation... but that's another topic entirely...
You also seem to be forgetting that slavery and blood magic go hand in hand in Tevinter... without slaves to power these rituals, how would the Magisters even be able to access the furthest depths of spellcraft? If I condemn slavery, does it not also follow that I condemn the use of slaves as power sources for dark rituals? Is it not apparent then that I believe in laws and oversight, at least to some degree? That one aspect of Tevinter culture, slavery, is the cornerstone for all of the magical abuses practiced by their rulers and nobility... remove that, and the majority of these abuses disappear as well (not all, of course... mages can still use magic to commit crimes like any other person...).
Hypothetically speaking of course... obviously it's more complicated than just banning slavery and then Tevinter becomes a paradise... that's not what I'm trying to say at all.