I cannot be too grateful to CS Lewis for his role in my conversion to Christianity - which was substantial and decisive. Indeed, my own trajectory into Christianity was broadly similar - in that it was 'philosophical' and went from theism, to monotheism, to Christianity; and proceeded mostly by logical argument with myself.
However, Lewis's Christianity remained highly philosophical - and indeed Lewis's Christianity is actually based upon the acceptance of some abstract philosophical principles - in particular the Platonic/ Neoplatonic (Boethian) concept of eternity as outside time - which is required in order to make sense of reconciling free will and omniscience.
That this was foundational to Lewis can be seen throughout all his writings; and even in the Narnian books for children - when The Last Battle ends with a very detailed description of the philosophical basis of Christianity - and a story-analogy for the relationship between Heaven and the mortal world: Plato is even name-checked by The Professor.
So, there is no doubt in my mind that Lewis was not only a philosophical convert, but continued to base his Christianity on philosophical concepts which are abstract and eternal and unchanging.
That is no longer the case with me - my Christianity is now based-upon relational concepts and a narrative understanding of history - I see God as primarily a Father, our Father - our relative in some sense; and therefore a person with a certain disposition, motivation and intentions; rather than a metaphysical/ physical entity with certain properties.
I now understand God's love for me and for Man as essentially like love as I know it; rather than love being an ultimate force or structuring principle.
And I feel no need to have my Christianity underpinned by explicit and abstract philosophical assumptions - for example concerning time. My metaphysical assumptions (that is, my basic assumptions which structure the understanding of reality) are now not philosophical. Philosophy and logic are still there but not as foundations, but further down the line as properties.
So, I would now distinguish apologetic and evangelical tactics from strategy; Lewis's tactics for explaining Christianity and winning converts are clearly effective for some people in some situations - indeed among intellectuals he seems to have been the most effective individual writer of the twentieth century.
But this approach is limited, and not necessary - indeed far more converts have been made by evangelical Protestants and Mormons, whose method is (to summarize crudely, in order to conflate the two rather distinct systems) based upon establishing a felt personal relationship with Jesus Christ, as validated 'emotionally' rather than rationally.
So Lewis was my original Christian mentor, but I no longer regard him as the major influence - and indeed feel Lewis 'got stuck' in that primarily philosophical mode which happened to be the way that he became a Christian - but which is not necessarily or usually the best way for other people to become Christians and even less is it necessarily the best way to remain a Christian and embark on a path of spiritual progression or theosis.
(Of course Lewis never would have claimed exclusivity - he was just doing what he could, as best he could; and he did it better than anyone else).
However, I think Lewis was led to the error of believing that some Platonic philosophical assumptions (such as out-of-time eternity) were indeed foundational to Christianity as such - since he included them in his Mere Christianity broadcasts and books.
In this I think Lewis was simply mistaken - since he did not know - or to the extent that he knew, did not appreciate - that Christianity has been, is, and can be non-philosophical - underpinned and built upon other things than 'philosophical'' principles.
Indeed, philosophy never ever needs to be mentioned in Christian discourse! - unless people ask about it, or our troubled by it.
Platonism is not Mere to Christians!
And this is something to be grateful for!
NOTE - It must be understood that I love CS Lewis the man and his writings, perhaps second only to his friend JRR Tolkien; I have read pretty much everything Lewis wrote - much of it more than once and some of it many times; I have also read a large swathe of biographical and critical material. So there is no need to defend Lewis against attack by me: I am not attacking him!