What Digital Marketing Services Are Best For An Agency to "Package Up"?

We have been running an online PR agency for eight years and have been extremely successful.

I'm taking a few co-op students on over the coming year, from local digital marketing programs, and would like to deploy them with a bit of a "side hustle" to see if there's enough revenue to keep some of them on in a new arm of our business.

I'm noticing, through in-person networking, that lots of local businesses either struggle with their digital marketing, or don't have time for it/understand it. But still, they know they need it.

I'm toying with the idea of setting up a small side business that just offers pre-packaged digital marketing services. - not necessarily to businesses who have online as their place of transaction, but local players who want that online presence.

Goal is to take advantage of a recurring monthly revenue model, and try to offer services at around $500/month, which our research shows is what small locals are willing to pay for their digital presence.

Question is - what kind of genuinely valuable digital marketing services are best put into a $500/month package for local businesses?

Just trying to gauge what kind of skillsets are required for such services, and if the incoming Co-Op students could manage it.

Thanks!
J.