These are the terms you've used (accurately) to describe these men and give them creditability, but that doesn't mean their opinions are to be accepted without challenge.
Kingsley, though a gifted man 'was sympathetic to the idea of evolution, and was one of the first to praise Charles Darwin's On the Origin of Species...(and) stated that he(Kingsley) had 'long since, from watching the crossing of domesticated animals and plants, learnt to disbelieve the dogma of the permanence of species' so on that ground alone I'd be suspicious of any of his theological musings.
If Kingsley's attack on Newman was more personal than theological, he should have been blasted out of the water. Newman's personal honesty, I think, is demonstrated by his eventual move to the Catholic church rather than remaining a 'Calvinist Anglican'.
Whatever descriptives that can be attached to these men or any of us, whether scholar, devout Christian, Cardinal, or Pope, if our beliefs do not square with the scriptures then we are just simply wrong no matter how 'reasonable' or comforting those beliefs may be.
I was in a church where there was no final authority (ECUSA) and of course it has simply degenerated into pitiful warring factions, most of which have forgotten Scripture and Tradition entirely.
A very fine Catholic priest, a true gentleman, threw us a lifeline into that wreckage.