I’m recalling that banana bread originated as something much less sweet and more savory?
I’d serve something else as a dessert and use that as a breakfast bread toasted with a thin spread of jam.
Though that banana bread pudding idea does sound very tasty!
I once used cayenne pepper instead of paprika on baked chicken. Very generously. Inedible. Even after the skin was removed.
I might cut it up into chunks and use it as the cake part of a trifle.
The chocolate is actually cocoa. Plain cocoa does not taste good.
I guess it depends on what one gets used to if not sweet enough. I’ve used a sugarless recipe that used 1/4 c of cocoa powder ymmv.
I do not add sugar to applesauce when I make it, nor to my stewed rhubarb. I also like cranberry juice with no added sugar.
Serve ice cream over the unsweetened cake.
Soften the ice cream first so that it evenly runs over the cake. Add cherries 
to decorate and add sweetness.
It’ll be great.
I made the syrup and poured all of it over the cake. I’ll taste-test it later; if it passes, I’ll bring it tomorrow evening.
It still doesn’t taste good. I’m going to dump it out in the yard, for the animals that hang out around here.
Too late to the party, but I’d have suggested using a meat syringe to inject the simple syrup into the loaf.
Our chickens love it when we have a cooking failure.