If you're looking for a quick and easy way to expand your rowing exercise selection, definitely try the standing 1-arm cable row with offset kettlebell hold.
Holding a kettlebell in the racked position on the non-working arm not only adds a core control element, but also facilitates thoracic (upper back) rotation away from the rowing arm. We know that left thoracic rotation works hand-in-hand with right serratus anterior recruitment (and vice versa), so this is an awesome progression we like to use with our throwing athletes. You could progress this particular version by adding a bit more upper back rotation to the left on the eccentric (lowering) portion of each rep.