I realize this is like "alias inception", but I think it could be useful to have like "category aliases" such as "newsletter" or "finance" and then also have the ability to also dynamically add a +xyz suffix. For example, I have a category alias "newsletters@slmail.com" and I am signing up for Bob's Newsletter, I could dynamically use "newsletters+bobsnewsletter@slmail.com", mostly to track whether Bob is selling my data, but without having to manage a bunch of unique aliases within the SL service.