Yes, yes, yes, do another course to add more tools to use in treatments! You'll most likely pick up Swedish much too easily, find you are quite familiar with a lot of it and wonder why you bothered.
If you're going to do another course, you've got the lighter styles from the aromatherapy training. Sports massage will give you a better understanding of how to get more thoughly than Swedish, you might not do a sports massage ever again after you finish, but you will be able to include sports massage techniques when required and some will almost always be required, it's the nature of modern life, either bad shoulders and neck from posture in front of computer screens, or lower back, or dodgey knees. Add essential oils into a massage that has the sports massage moves as customised for the client as they present, and you will have a very stong base to treat from, from sporty to light with a bit of accupressure, lymphatic etc.
Lymphatic drainage is light work, but incredibly effective, though it tends to be a much smaller market.
If you're young, do the sports massage, if you're older and sports massage sounds a bit too much work, go for lymphatic, more chance to sit down
If you want something more entertaining (I wanted to scream by the end of my aromatherapy course with 3 of this this side, 3 of this that side, then 3 of that, then 3 of the other, I was bored silly) do something like lomi lomi, or No Hands, No Hands will get you in deeper without hurting yourself and you'll pick up a lot from it, lomi lomi is great.
Having said all of that, I still do a lot of the aromatherapy facial moves in any treatment I include the face in (with a lot of Ayurvedic marma point massage). I do a lot of the aromatherapy body massage moves on pregnant clients, they usually need something lighter and more lymphatic stuff. I use some of the aromatherapy moves in every treatment as the soothing calming warn up, relaxing after a bit of sports type work and wind down at the end.