Basically you want your signals to arrive at the same time (with some margin), and the propagation speed on L1, L3 and L6 will be different.
So the only way to go will be time matching.
However, if all of your signals are on the same layer, you can do length matching as they all have the same propagation speed.
Most (advanced) layout systems will allow you to either one. For really high speed signals you also have to consider the timing inside the device. (Die to Pin).
As an Expedition user i can set the delay for my via's and the system will use those delays for timing calculations. I assume that this option is also available
in other (advanced) layout systems
Make it a habit to use time, That is what you really interested in.