I know that https://help.ghost.org/article/21-migrating-from-wordpress-to-ghost is not up to date, but I think that a good Ghost adoption focused tool should make it easy for people to migrate a blog from WordPress to Ghost (so that document needs an update, as well as the WP plugin, I guess - tried it out and it still exports and imports content ok, but is missing some features).
I manually migrated a very small blog from WP to Ghost and I enjoyed the experience, but am considering migrating a bigger one (150+ posts or so). I’ve tried it out on a Ghost test install and it basically works, but it could work much better with some small modifications.
One feature that I think would make sense for this migration is to allow users to choose whether they want to migrate tags to tags or rather categories to tags (usually, content in WP is structured in categories rather than just tags - as default taxonomy). As it is now, you need to recreate old categories as tags and reassign posts to new tags, while maybe removing the old tags (if they make the tag structure too complicated). This could also solve the issue of migrated permalinks being domain.com/category/title/ in both WP & Ghost cases (if also Ghost would have this native option to rewrite tag categories).
Another useful feature would be to export and import pages as well (directly as posts or as posts with the page attribute already set). I’ve looked through my test migration and I don’t remember seeing the pages in there (so those need to be recreated manually). LE: Nevermind this, it’s already there.
And a third useful feature would be for the export script to automatically replace /wp-content/uploads/ to /content/images/ so users don’t have to run a find and replace in the export file (I did this and I had to factor in the escape \ characters for / as well as the tutorial wasn’t mentioning this little hiccup).