Fact 1. Already addressed, he said it after receding the curse seal so we know the context.Fact 1. Sasuke said his base body was adapting to the power
Fact2 , Sasuke was obviously referring to the cm , ADAPTING to his base body.
Fact 3. Kabuto notes the strengthening of his base chakra.
LOL Sasuke's base chakra obviously wasn't always that powerful , enough so to scare the crap outa kabuto. Clear increase in chakra levels is clear but But anyway man believe wat you want , not about to go in circles.
Fact 2. Yep, so he can use curse mark powers with no problem when he can adapt to it fully.
Fact 3. Well yeah, Uchiha chakra atrgethens the stronger their eyes are. Last time I checked base chakra has Yin and yang in it. Yin of Sasuke was strengthened by achieving 3T, so it makes sense.