This has been a huge issue lately and is being discussed on our internal website.
The main problem is, thanks to Delta consolidating most of their ground handling under "Delta Regional Elite", the SOP of this outsourced company does not allow them to load ballast on Pinnacle flights. All CRJ-200's face the same issue with the need for ballast on full flights, unfortunately Delta doesn't really care if you miss your commute and Pinnacle is powerless to do much about it. The most the crew can do at these affected stations is notify dispatch, who then comes up with a min cargo number. Also the gate agent and FA can be extra vigilant about making sure as many bags as possible get gate checked.