Esther, one thought (from someone that isn't a content marketer) is that your outreach should address their problem (as they see it).
I think it makes sense that you are focused on the words themselves because that is the world you live in. But the words themselves aren't the problem as the prospect sees it. What is the problem? It's probably how little traction/engagement their social posts are getting.
If you were reaching out to me, I wouldn't want to have you nitpick words, I'd want you to speak directly to a problem I am experiencing (lack of traction/engagement with instagram) and make clear you have experience fixing that exact problem.
For example, if the posts in question have a handful of likes, make clear you understand how frustrating it is trying to execute an Instagram strategy only to hear crickets....then segue into how your services solve that problem.