Propellant Spreadsheet(Updated 18/10/2017)

A small correction to your formulas - your density for F-H seems to be far higher than it actually is. Since 1 kg of hydrogen and 18.8 kg of fluoride fit into almost exactly the same tank, you'd expect the density of F-H to be close to half of fluoride, but yours is around 95% of fluoride. The density I got for my calculator was 787 kg/m^3 which at least sounds plausible. Fixing the density should increase F-H costs a bit, since the tanks will be heavier as a result, but I don't expect to see huge differences.

Another note for tank mass ratios is that you can quickly check the mass ratio for an optimal tank in-game, since the ratio only depends on the propellant and tank dimensions. Your numbers for tank mass are pretty close to mine though, so again you probably won't see a big difference if you use the precise numbers.

I think your fuel mass formula doesn't take tank or armor mass into account right now. You can easily solve the required mass ratio for the whole ship from the rocket equation, as you did in your calculator. However, dry mass is not the same is payload mass. Dry mass should contain fuel tank mass as well as the mass of any armor and engines in order to give the correct required fuel mass. This means you'll need to solve for fuel mass in a linear equation that looks something like follows:

           mass_ratio = m_wet / m_dry
             m_wet = m_dry + m_fuel
<==> m_fuel = mass_ratio * m_dry - m_dry
             m_dry = m_tank + m_engine + m_payload + m_armor
             m_tank = a * m_fuel
             m_armor = f(v_fuel, v_payload)

I didn't bother with the increased armor requirements stemming from fuel tank volume, but factoring for just the fuel tank mass gives you some increased accuracy, especially for the lighter propellants. With heavy propellants with fuel tank mass ratios of >100, it doesn't really make a noticeable difference except at the extreme dv ranges.