The throat at Paddington lends it self better to quicker in and out paths than Euston, Euston is cursed with tunnels at Camden which cramps the amount of flexibility that was built into Paddingtons 6 high speed bidirectional lines that run out for over 2 miles. Also at Euston they are stuck with the Watford DC▸ lines almost in the center of the station with associated underpasses.
Valid points, Electric train. Though, on a point of accuracy, lines 1-6 aren't over 2 miles in length - more like 1.5 miles.
Its been a while since I wandered

about in that area I think it was when the wires for HEX were being commissioned. Paddington has one of if not the best routes into in of all the major London termini, no tunnels or bridges over the Thames and from memory the over bridges that are there other than Great Western Rd bridge at Westborne park do not have any supports in the permanent way