That may work, but you may find it tricky to avoid getting worn down by his AOE attacks (assuming heroic), R2 really does help you spread the pain around with targeted foresight (yes, you can do the same with JTR but that is cutting into damage potential since you won’t be calling bb8 every time, plus you are increasing RNG factor since you can’t hide a wounded character behind a smokescreen while they recover).
Curious as to what Rebel team (and for which phase) you are building that is worth dropping an optimized JTR squad and your potential Chex mix team for phase 3 (not that there isn’t better options for phase 3 now, but it is still one of the easiest teams to build to contribute your share)?
Right now the optimum phase 1 (or phase 3 they can pull over 10% of heroic there as well) is JTR, BB8, RT, R2, C3PO.
I suspect that Finn could replace one of those after his rework (I guess threepio), but we will have to play around with the line up to see how much we can squeeze out of it in the various incarnations.