Also, macros cannot be used in Scheme to implement implicits because implicits, like type classes, rely on static type information. I have actually heard of an attempt to implement type classes in Scheme and it required manual type annotations in all use cases. And, while it hasn't been formally proven, intuitively implicits and typeclasses feel like the kind of languages features that would be difficult, if not impossible, to implement with classic macros.
I feel like you have some pre-conceived notions, both about what macros can and can't do, and about what affect they will have on the Scala language when added. However, as others more knowledgeable than me have already pointed out, macros have already managed to simplify the language as is, and their full potential has yet to be untapped. I would suggest giving them a chance.
Also, macros cannot be used in Scheme to implement implicits because implicits, like type classes, rely on static type information. I have actually heard of an attempt to implement type classes in Scheme and it required manual type annotations in all use cases. And, while it hasn't been formally proven, intuitively implicits and typeclasses feel like the kind of languages features that would be difficult, if not impossible, to implement with classic macros.
I feel like you have some pre-conceived notions, both about what macros can and can't do, and about what affect they will have on the Scala language when added. However, as others more knowledgeable than me have already pointed out, macros have already managed to simplify the language as is, and their full potential has yet to be untapped. I would suggest giving them a chance.