Doesn't concern me, i'm predominantly driving HSTs!
Just get angry when I hear that apparently the 230s will not be considered for franchises in the north, yet they are seen as fit for the south west. No wonder the economy of this area has gone to pot, whilst the north moves from strength to strength....
I dont think its a case that the 230s were not considered for the North, its almost certain that all bidders would have considered them. However with Arrivas winning bid it probably became apparent that the 230s could do little more than replace some of the Pacers, and that new stock would have to be ordered anyway not only to replace the remaining Pacers but also provide the increase in capacity they were committing to, as well as provide the Northern Connect services that are planned. So rather than buying a mix of new build and 230s along with the planned cascades, they simply opted for new builds and cascades, probably negotiating a better price for the new builds (and possibly leaving the door open for further orders).
What you also have to remember about the order with CAF is that it is a mixture of DMUs & EMUs, built to similar specs but with the obvious different traction types. This will make it easier for both builder and customer, especially with maintenance / training as there will doubtless be some similarities in the unit builds, on-board systems etc.
But most of all, whilst there might be some routes where 230s could operate, many Northern diagrams see units on various types of routes from stretches of low speed branches to sections of high speed main, and everything else in between. Northern units can find themselves on almost any route at any time, especially during periods of disruption. Given that a large number of new routes will become Northern Connect under Arriva, I suspect one motivation for not ordering the 230s was that there might be a risk that one of these might end up have to be utilised in place of a regular Connect unit. By opting for new builds, as the Pacer stock is withdrawn the worst possible scenarios for these routes would be 150s, or more likely 153/155/156/158s (some of which will be in use anyway).
Of course none of this means that they are more or less suitable for the SWT branches. That will be up to the franchise holder to determine. But as far as the Norths problems goes, the 230s were never really more than a short term sticking plaster solution. Sooner or later they would either have to be life-extended, or withdrawn to be replaced with new builds.