I can't say I am an expert myself. However I think FexFx has a long explanation of his choices for speed balances and his mod is already included. What I think is advisable is to have a starting point that depends on previous work. So we either use the linear formulas of the vanilla BTS, or we start with the adjustments FexFx has made and try tweaking from there. To try helping I will go through the analysis FexFx offered and compare his figures with the ones in the mod for I am convinced that his effort shouldn't be wasted. And I guess he would welcome any successful tweaks of his results.