@Gargron The data in !OStatus travels with HTML representation. If you create the HTML representation in a way that puts <img/> tags where the image links are (you know, like blog posts) then it's shown correctly.
...except that microblogging sites like !GNUsocial tend to ignore <img/> tags because we haven't bothered matching them against the attachments and presenting them locally to avoid third party tracking...
My point is OStatus is perfectly fine to represent interspersed text and images (because it's HTML) and it's only up to the client to generate good HTML and the subscriber to trust it. Just use some sort of WYSIWYG, like Wordpress, to post your stuff and let PuSH/WebSub distribute it for you (or implement WYSIWYG editing in Mastodon for example).
cc: @waha06x36 @halcy