If you regard your cards as an investment, what the hell are you doing playing with them in decks? Use proxies if it's that big a deal. I sleeve my cards (singly) because I don't want them totally wrecked and I play with transform, but if I want to keep a card in really pristine mint condition, it stays in the box inside a hard case.
A big change which forces everyone to redesign their decks needs to provide big benefits to justify it. My own pet issue is cutting life totals to 30. That would rebalance the format, giving aggro a desperately needed boost, forcing combo to watch its back, and speeding up games considerably. Even so, it would be a huge change, not to be made lightly or without careful testing.
Making it possible for people with expensive cards to double-sleeve and still shuffle easily is... not in the "big benefits" category.