You did the right thing, as for me ail_inv=1 wasn't good but I need elev_inv=1
Maybe it's a difference between HK-FBL100 and V922 or the HT8.
But if the model.ini I provided helped you to quickly fligh your bird,
It was my purpose of posting it.
And I'm not sure of the pitch curve, cause it's a pain in the ass to edit the ini then load it in TX and try it on the bird...
I dunno how to edit pitch curve directly on the TX under deviationtx ...
But it certainly need some more modification, because on the RTF the bird is more stable in hover on the altitude than my settings under deviationtx and HT8 v3