In my bread puddings I leave the flavors up to chance, at least a little bit. I get the day old pastries from the local bakery and use those in my bread pudding. So if it was apple pancakes it’ll be an apple bread pudding, if it was cherry filled it’ll be a cherry bread pudding. That being said I found that some lighter and not as sweet breads needed to be in there, i.e. croissants, to not overwhelm it. I’ve also put lots of fruit in my bread puddings. Bananas are great, but also raspberries, blueberries, mangoes, or whatever you find that may work well with bread.
And yes, I also found out that the waterbath improved the texture quite dramatically.