There are a number of things you can do to boost flavor, which is always going to be subjective.
1. Fiddle with the power settings used for your current coil. Some flavors do better at slightly higher or lower power than others.
2. Experiment with resistance, same reason as above.
3. Increase your surface area. Use more wraps of slightly lower gauge wire if you want to aim for the same resistance.
4. Micro-nano coils, which have different definitions depending on who you ask. But this includes basically anything 1.4mm and smaller, such as coils wrapped around syringes down to about <.5" in diameter. Such a smaller inner diameter does make wicking a tad difficult for this kind of set-up, though.
5. Stainless steel wire. I still like 316L.
6. clapton or fused clapton coils (with or without SS). Fused may be a bit big for the RBA to accept, but it will easily take decently sized claptons and possibly smaller fused claptons.
7. If all else fails, it sounds like you DIY, so increase your flavoring for juices used in that tank.
These aren't the only things anyone can do to try and boost flavor, but I can't think of much else to do in that RBA. You could experiment some with some different wicking techniques or coil orientation; there's a chance vertical coils and the resultant wicking choices would work well in there. I have and use this RBA but haven't had trouble getting good flavor from stainless claptons, which are my go-to anyway.