Two questions.

[Fox666]

PS required to easily use KKx10: 20.000. - this is based on that I think Ginyu could only access Goku's physical strength, which is why his BP only was 23.000, while in Goku's body, simply because Ginyu being an alien and all has a different way of powering up, which only relies on physical strength, meaning he can't acces Goku's ki strength(which is 67.000, since 90-23=67).

Goku don't "power-up", it's the opposite, he is able to manipulate his Ki to store energy. In other words, the Earthlings can only decrease their Ki, not increase it.

Ginyu only has 1/4 of Goku's power because he was not used to that body, eventually he would gain access to the 90,000...

[dbgtFO]

PS required to easily use KKx10: 20.000. - this is based on that I think Ginyu could only access Goku's physical strength, which is why his BP only was 23.000, while in Goku's body, simply because Ginyu being an alien and all has a different way of powering up, which only relies on physical strength, meaning he can't acces Goku's ki strength(which is 67.000, since 90-23=67).

Goku don't "power-up", it's the opposite, he is able to manipulate his Ki to store energy. In other words, the Earthlings can only decrease their Ki, not increase it.

Goku powered up vs. Nappa...
And I don't understand your second point, since Krillin was shown to able of "powering up" vs. Guldo and Freeza's minions.

Ginyu only has 1/4 of Goku's power because he was not used to that body, eventually he would gain access to the 90,000...

Ey it's my fanon, that he can't use Goku's ki strength .

[Fox666]

They powered-up to their full power because their power was suppressed in purpose... Ginyu don't know how to surpress his power and would only use the full power in their bodies.