I recently bought the RF24-105 F/4L as a compromise between aperture and size, the lenses you mention above would have been more to my liking
I’m still very happy with the 24-105, it is exactly what I thought it would be.
You must have got a good one, since there seem to be copy variations. Mine was just OK, but definitely not as good as the EF 24-70 F4.
Guess which one I kept, yet knowing that there are some very good 24-105 around.
As OpticalLimits often stated, it is far from easy producing an excellent "standard" zoom. Fact is, a standard zoom lags behind similar focal length primes. Not so tele-zooms.
Therefore, I'd rather see a 24-50 than a 20-60, less extreme is often better, meaning less optical compromises. Sadly, moderate zooms do not sell that well, think of the really great Sigma 24-35 F2.
But I still expect some good Canon surprises...