I feel like that's too much effort that would be better expended somewhere else, plus there are all the drawbacks that rabish mentioned.
Some of it isn't really too much effort. The loads between interiors and exteriors are a relic from Morrowind that I don't think any other developer in the industry would actually do something like that without hanging their heads in shame. Load times in general (except at the start of a play session) are actually started to become increasingly taboo,
especially in sandbox games, so Bethesda really should be doing
something to try and address them. That's not to say that Bethesda doesn't have to overcome some unique challenges to actually deal with the interior/exterior transitions, but it being uniquely challenging does
not make it any less important.
The same goes for character animations in general. While I can certainly understand not animating every single action that the player does, Bethesda's frankly been very near the absolute bottom of the barrel in terms of character animations for a long time. They don't need to have
astounding animations, but the quality of the animations in most of their games is outright embarrassing and that's something that really does need to be dealt with.