Hard Kombucha - yeast and honey

[ouranos]

I'm following the recipe from Northern brewer for Boozy Kombucha however it only uses yeast + optional hops + the sugar [ I used honey ] since I have a Jun SCOBY and it has lived a life of honey thus far.
Questions:

1. Other recipes suggest using barley and malt in addition to hops and yeast - how would addition of barley and malt impact the final product vs simply using honey + yeast + hops
2. 2ry fermentation temperature : am I correct to assume that I follow the yeast temp requirements vs the temp typically used for kombucha[ scoby already removed for 2ry ferment]
3. sugar vs honey: the recipe calls for sugar but I have been feeding scoby honey - i used honey to make the yeast slurry - how could this impact my final product and why could one one form of 'food' be more beneficial than another eg sugar vs honey
4. flavouring and carbonation: I I go directly from 2ry ferment to bottle without adding juice or other sugar source, would the ingredients thus far be enough to provide sufficient carbonation?

Thanks for your insights!