This should not be taken as a total response, it is only a theory, but I think it does not contradict anything that has been seen in the guyver manga.
first, the numbers of the transformations,
a gregole, it's 15 times. the strength of a human,
A ramotith, is 9 times. the strength of a human,
But here comes the problem, in the manga you have seen Gregor lifting a tank, only with his hands, in fact in the vignettes of the day you see zoanois that are more deviles than gregole lebantando automobiles.
and also the enzyme 2 that according to memory is a little more devil than gregole. I pick up a truck and I throw it easily,
from what I have theorized that, the transformations in the guyver universe are not of the human average, but of their maximum expression of force,
an example would be as if we took the maximum force of human potential, the captain america, and we multiplied it by 15, I do not know if this would be enough to lift the more than 30 tons of weight of a tank, but they already have an equi-balance,
by the way I have theorized a guyver with the strength to lift more than. 400 tons, if we take a bace of 4 tons in the human form, due to the maximum weight that has been seen lifting a gregole,
the tank seems to weigh about 49 tons, divide that by 15, and they will have one unit for humans after being processed,
with respect to, the guyvers, maybe because they are human without processing the armor when covering them, extrapolate the maximum potential of the guests without having to process them.
remember that we are talking about the maximum destruction weapons maciba created by an alien race, I do not think they were satisfied only with the regular human force.