Hmm... Tiramisu can be good, or awful (are you looking for premade, or DIY, I'm unclear?) I'm always a fan of crème brulee but I like it with a bit of fruit on top (wait, is a banana a fruit? I'm thinking it isn't, actually.) I have to say, I'm a huge fan of merengue and I didn't think I would be, but I like it, with a bit of chocolate or caramel (even lemon, possibly, though I can't seem to handle artificially flavored citruses, they don't taste right to me) merengue with coconut is also impossibly delicious (IMO), the coconut cuts the sweetness a bit and can be tasted along with the meringue. I'm a fan of greek yoghurt for some sweeter flavors.... That might be an option.
If you want to try DIY maybe ordering some tasters might be helpful, if you are looking for premixed e-liquid, I am very little help as I made the switch to DIY very early (and I am so glad I did). But, good luck with whatever you decide. Maybe you want to keep banana and do like a banana nut bread flavor (I'm pretty sure you could find a premade one) or something like that as well.
Good luck deciding, and whatever you choose, I'd start with smaller quantities first, whether it's concentrated flavors or a new juice flavor.
Congrats on your 18 months of
vaping, that's fantastic!
Anna