This will be OT, but I will jump in, because I see here little bit mixed informations :- ))
No, French revolutionaries did not think about better definition of second, they even did not think about coherence of units at all (that is what means that force = mass * acceleration; energy = force * distance; power = energy / time etc without scaling by funny constants). Coherence is only little more then 100 years old concept comming especially with SI metric system. SI is that what we use, there are several metric systems known in history, and most of them are NOT coherent. For example BAR is metric unit for pressure which is NOT coherent, it is aproximately equal to atmosferic pressure. But Si metric system has another COHERENT unit Pascal which is [kg * m^-1 * s^-2].
That funny constant 9.81 for G acceleration is not an exception from coherence. Metric SI system does not know any "G" unit, it has [m * s^-2] what is again coherent (automatically), object of mass 1kg will need force 1N to accelerate 1m/s/s. That constant 9.81 is not unit, it is property of our planet, SI system is the same on Mars or Venus or Moon and they have certainly different gravities :- ))) ... but object of 1kg will need still the same force 1N to accelerate 1m/s/s.
BTW during my life and education in schools university etc, I did not meet unit kgf ... ever :- )))))))))))))))) yes here is non SI unit kp (kilopond) but it is unit which is not used in SI system and it is mentioned only on place of physics books in history part where is explained unit Atm or Bar (pressure) as kp/cm^2 what means aproximately atmospheric pressure, just to give students overview how strong pressure it is :- ))