The bio/non bio thing is absolute baloney, the U.K. is the only country in the world where bio and non bio are sold alongside each other and non bio aimed as being for “sensitive” skin.
In other countries, non bio simply isn’t sold (in the few other countries it is, it is only one or two products and it is for wool and silk not sensitive skin); we have the good old British Press to thank for that.
However, what isn’t so much baloney is that detergent perfumes can cause reactions, especially on delicate skin like a baby’s, so would definitely look for something less scented, all the products you currently use are very highly scented, which is fine for mature skin, but maybe not for baby.
I would personally recommend Fairy washing powder, which ironically is non Bio, but I don’t buy it for that, it’s a good wash powder, has a gentle scent and genuinely does wash clothes softer, even if not using a seperate softener.
Yes would definitely not recommend the scent boosters for baby laundry.
There are a few softeners aimed at baby laundry, Fairy fabric softener or Comfort pure are the 2 main ones , They’re both nicely gently scented, and I also like Sainsbury’s “gentle” softener, but to be honest, softener isn’t really needed at all and you can use a standard one, like standard Comfort or Lenor, but maybe not the stronger scented ones.