There is most definitely a need to resolve the West Yorkshire traffic problem. It's a nightmare. I'm not sure that this is the best way, and (as Peter says) the Flockton link would be a good idea.
IMHO the big problem is the M62/M621 junction (rather like M60 J13 causes the vast majority of NW problems), especially the approach from the west - so a solution to it would have to link to the M62. Chris Marshall came up with the idea of a motorway from the northern point of the M606 to a (redesigned) M62/M621 junction, and I rather like that idea. Bradford needs to be better served from the east, and so a raft of motorway building around this area would probably alleviate the problem much better than the current managed motorway situation between J25-J30 of the M62.
Agreed - I think that the Flockton Link would be the logical 'first step' in improving the general situation in W. Yorks, and should have been implemented decades ago - compare the density of the motorway network in W. Yorks to that in NW England, as a comparison. The Flockton Link would have the effect of 'dragging' traffic (going from Bradford & west of Bradford to southern destinations) to the Link, thereby alleviating the mentioned section of the M62 . .
. . And the suggested new link 'from the northern point of M606 to the M62/M621 junction' is also a good idea, and may initially be a good 'quick fix'
Eventually some serious inter-urban Bradford / Leeds DC's need to be considered, which would have the additional effect of 'dragging' some of the Bradford / Leeds traffic that would've used the M62, northwards to a better and more-direct route . .