Does the Darwinian theory require modification or replacement?
Yes, as with all theories. No theory is perfect, all require modification when newer and better evidence is found. This may alter of overturn a theory. As with the overturning of Phlogiston with Oxidation-reduction or the modification of the Periodic Law with the discovery of the proton. All theories are falsifiable, Evolution has been modified many times since it's inception, but there is no indication that there is any competing evidence that would overturn it.
There is no better love between 2 people than mutual respect for each other WT Young, 2002
Who gave anyone the authority to call me an authority on anything. WT Young, 1969
Since Evolution is only ~90% correct it should be thrown out and replaced by Creation which has even a lower % of correctness. W T Young, 2008