Yeah, unfortunately it's the gluten that provides the texture and crumb in baked goods using wheat flour. I personally add xanthan gum (1/2 tsp per cup GF flour) to provide the crumb.
My go-to GF flour mix is rice + tapioca flour + cornstarch (6:1:1), but it is bland and tends toward gritty. For protein, you could replace 1/4 to 1/3 of the rice flour with bean or soy; these also help increase the density of the baked good. I prefer soy; bean is a much more noticeable flavour, but you've got the spice and ginger to balance it. I've also used sorghum in the mix; it's a lighter flour that adds extra sweetness.
And I agree with fred_mouse; you may have to play with the liquid.
Re: Yes!
My go-to GF flour mix is rice + tapioca flour + cornstarch (6:1:1), but it is bland and tends toward gritty. For protein, you could replace 1/4 to 1/3 of the rice flour with bean or soy; these also help increase the density of the baked good. I prefer soy; bean is a much more noticeable flavour, but you've got the spice and ginger to balance it. I've also used sorghum in the mix; it's a lighter flour that adds extra sweetness.
And I agree with
(Edit: a word)