Yup, I would put them inline/slightly downstage of the guys in front and focus across. This let's you do things like one color from one side and one from the other to break up the body and added depth. Just side light and no front light also works well and gives a different feel. You can even try just side light from one side for dramatic effect now and then. Creates nice shadows on one half of the face.
Side light also generally works well with back light and complements each other. You can have just sidelight and back light on for whole numbers. Sidelight has a very flattening/evening out effect vs using front light which is generally hung over head and pointed down. This creates little shadows on the face and with clothes. Sidelight setup correctly gets rid of those shadows.
Color is also very important in getting the most out of sidelight. Contrasting colors with back light tend to be very effective and create more depth. One of my favorites is amber side with blue back or visa versa as seen here:
That is R21 side light with full blue LED from behind. Also,
here is the tail end of the video I was going to show. That dance was pure R27 side light with green and purple LED back. Notice how flat she looks. Start of the following dance is also just side light and back light, so you can see the different shadows it casts with people running across the stage.
Also, thanks for your complements. That was a fun show I did 4 years ago at this point. A shame I don't have good pictures of it.