You said that Australopithicines are a mosaic of humans and other apes and you describe some features that are human like and some features that are like other apes. Isn’t that exactly what we might expect from a transitional species? You are trying to have your cake and eat it. You claim that transitional don’t exist but then we we find one and you claim it can’t be related to humans because it has features of the species it transitioned from.
That’s deeply dishonest.
If that's the case then I apologize. Yes you might expect a transitional to have features common to both. I can't argue that there isn't an apparently clear set of transitionals leading up to humans, but neither can anyone say that is conclusive evidence, because it could still be the case that they are unrelated.
To be fair, it is difficult to come to a definite conclusion because of the incompleteness of the fossil specimens available. In time I'm sure more will be found.
One aspect of the Australopithecines that puzzles me is the ratio of upper and lower limb lengths. I wasn't sure there were any specimens which have a complete upper and lower limb, until I saw 'Little Foot'. It has recently gone on display and appears to have a roughly equal length upper and lower limb, which poses questions about how it moved. Hopefully more details will emerge and we will have a better understanding in future.