Nominal is just a name, it’s not the actual cell voltage. Things saying “3.6V” or “3.7V” are all 4.2V cells, generally. Both of those work for 30Q cells, which are not the best cells you can get. This is mostly to differentiate them from LiFePO4 cells which might be named “3.2V” but are typically charged to around 3.65V. (not to be confusing or anything)
It also depends on what you want. Do you want to be able to diagnose problems without taking it apart, by seeing battery data on a phone, but also have the power to break it in more novel ways? Then you want a smart BMS. Otherwise, you don’t. Those are also often larger physically and have a larger price tag. Especially with the 30Q cell choice I would highly recommend it, but don’t change settings with it if you don’t know exactly what you are changing, why, and how it can break it.
Not everyone, but there are advantages and disadvantages:
Yes, I would emphasize the word “healthy”, like double it. At least.
So first figure out whether you need discharge or bypass configuration, then figure out whether you need a smart or dumb BMS, and then we can suggest specific models if needed.