As you can see on my site: at the time of writing I don't have them. I do show a line with a summary of the post. It shows the author's name, the post's title or just 'a post' if nothing is available. I have been planning for a long time to add context to it, but I would only do that on the detail-pages: on feeds I would keep it as is. I think that might work very nicely for your design too! But: as long as you show any preview at all, you're not cutting the complexity of the Mf2-fetching.

Addition: I like to save the context for my own archive too. My site even saves a copy of the image if I like a photo-post, even though it does not display. So: I myself would not want to loose the complexity of the Mf2-fetching, for it has other benefits.