Neuvilette or Columbina in bloom team? As a driver?

Columbina is gonna be incredible for teams that trigger lunar reactions, so she’s pretty much a must-pull if you have Lauma already

Use Columbina. Neuvillette damage is not amazing in a double hydro double dendro team, even at C1R1 if you're going by todays standards.

In a bloom team the hydro character is the driver, so neither, because you want the driver to be built with full EM (1k+) and neither of these characters want that.

Also, you don't *really* want Columbina in a Lauma Bloom team, because Lauma's passive that allows blooms to crit only works when she is the only Nod Krai character. Sure Columbina makes up for that damage by being on-field but at this point it's no longer a bloom team, it's a Columbina DPS team.

Finally, bloom only has one team: Nilou bloom. If you don't have Nilou, you don't have a bloom team. The default reaction is too slow and not powerful enough to be worth it, *especially* if you plan to use suboptimal characters for it like a driver that's not built with EM. Your next best bet is Hyperbloom if you have either kuki or raiden, and again if you have neither of these characters you're out of luck.

At this point you're better off ignoring the reaction entirely as far as your rotation goes, you need it to charge your Lunar Bloom counter, not for the reaction itself to do anything meaningful. You're not building a bloom team, you're building a whatever team that happens to trigger blooms from time to time and those blooms will do a negligible amount of damage in your rotation.