Hey {{first_name}},
I'm just checking in to see if you had a chance to read my last email.
If you're open for a phone/video call on [[day proposed]], let me know!
Best,
[[your name]]
Hi {{first_name}},
How are you? I can't believe it's been [[time frame]]! I just took a look at [[their site, recent work, blog, social media feed]] and [[brief but specific compliment]].
I am reaching out to see if you'd be interested in meeting up for another [[idea exchange/coffee chat/whatever term makes sense here]].I also would love to [[find something you can show them that may be of use to them]] that you might find useful as well—and of course use it as an excuse to catch up!
Hope all is well,
[[your name]]