What's the point of keeping legacy? If some services are still not compatible with Bech32 then Nested should work just fine. Your GUI edit looks pretty good but it would confuse newbies which probably don't see any difference between these three types of addresses. Don't you think that there should be a short description of every type of address? I guess that Bech32 won't be a standard wallet because some services still have problem with this type of address.