I like this my only suggestion is not to caramelize the honey, or if you do only very lightly. i dont think the caramel flavors will mix well for a tropical mead. maybe a banana foster kinda attempt i would caramelize the honey and oak it to simulate the rum (side note i may have to try that). also with my experience from melomels i think you are doing the right thing with delaying the addition of the banana , but you might not get enough flavor in just 4 days. so play around with that if you have the luxury, or even stagger your addition of banana, maybe after 4 you add 1 banana, and when transferring to the car boy add the other? up date us i like where this is going!