This is cool but I've started reducing my need for migrations by just serializing most of the structured pieces of the record into a text string (json for example), and only have separate columns for things that need to be joined (usually an id column) or selected on/indexed. I find this approach prevents me from needing to do migrations nearly as often. If you find that you really do need to index on a new field, adding a column is the easiest kind of migration to do.

Of course sometimes you do still need to which is where strategies like this come in.