I confess...

I read the whole damn book and I want the time back. Naming? He's up there with J.K. Rowling on that score.

No. His names are linguistically consistent, inventive, memorable, and serve fantastically well to give his creations depth and interest. There is a deep gulf of difference between the rhapsodical, haphazard, and random 'naming' that authors like C.S. Lewis and J.K. Rowling do.

His more "serious" writing failed to hit the scale of the ancient epics he was trying to invoke

I'm not sure what you mean by 'his more "serious" writing. Do you mean things like 'The Monsters and the Critics' or his academic research (which, by his own admission, he neglected)? As for his own tales, Tolkien would probably have taken it as a compliment to be told that he had failed in invoking ancient epics by quite some margin but still got a little way there. His admiration for much of this literature, particularly Beowulf, was profound. However, whether that is true or not, invoking these sources later turned out to be (and, I would argue, never was, although initially not realised by him) by no means his only motivation for writing.

not helped by the unsubtle Christianised spin (oh, and we have him to blame for C.S. Lewis).

There is very, very little in all of Tolkien's work that is expressly, or even 'subtly', Christian. Some commentators, like Joseph Pearce, have constantly tried to overplay the Christian angle, but I'm afraid I consider that approach nonsensical. There's no doubt that for various reasons Tolkien was a committed Catholic, but another brand of Christian commentator has lamented precisely the lack of Christianity in his writings.

What there certainly is is an overlap with Christianity on some core themes, but certainly not ones exclusive to Christian thinking. For instance, I would argue that every single philosophical and theological theme found there is basically Neoplatonic (largely Augustinian, which is no surprise given the Catholic tradition in which he grew up), and that apart from his mother's fate, the fact that Catholicism is and was a minority faith in this country, and the fact that he greatly enjoyed the Latin mass, this core theology is really what attracted him to it. The one exception to 'Neoplatonic only' is his belief in the Fall (again Augustine), but I personally think that the figure of Melkor is a vast improvement on Lucifer and the story of Fëanor a vast improvement on Adam and Eve. Obviously, whole libraries have been written on every aspect of this by now.

As for Lewis, you may be aware that he and Tolkien fell out long before Lewis' early death precisely over the issue of his writings, which Tolkien disliked more and more as the Space Trilogy and then Narnia progressed, not to mention his Christian writings, with most of which Tolkien disagreed profoundly. It was one of his greatest disappointments that Lewis simply returned to Anglicanism instead of converting to Catholicism. While Tolkien initially did play a part in motivating Lewis to turn back to Christianity, he most certainly didn't cause the vast majority of what Lewis wrote from the 1940s onwards.

It would actually be more pertinent to blame Lewis for Tolkien, as his unswerving encouragement of Tolkien's writing, through the Inklings and outside of it, was probably the main push Tolkien needed, and his lack of productivity in his later years was undoubtedly in large part because Lewis no longer motivated him.