Well, I think you will find a variety of opinions on the Duke here and not all of them very positive. For my part though I have a genuine fondness for him. As an actor anyway. I suspect we wouldn't have seen eye to eye much politically.
The thing to remember about Wayne I feel is that his career as a lead actor spanned 5 decades and included a ton of material. Consequently, the style and quality of his films vary. As do his performances in them. But amongst the 100 odd films that he made were some indisputable classics in which he proved that he could genuinely act if given the right material and the right direction. His work with John Ford is the obvious example of this. In films like Stagecoach, The 3 Godfathers, Fort Apache, Rio Grande, The Searchers and The Man Who Shot Liberty Valance Wayne showed a genuine range as an actor, from sentimental comedy to pyschological drama. Films like these counter any criticism directed at him as a 'one dimensional' ham in my opinion. But he didn't just shine when working with Ford. Other stand out films with different directors would include Red River, Hondo, Rio Bravo and True Grit. Again, all stand out films which demanded variety from Wayne as an actor.
He made some duds too of course and later on in his career (1960s and 70s) probably became somewhat of a charicature of himself. But any actor who could boast a filmography which included the above titles deserves respect in my book and has to be included in the pantheon of genuine stars of the western genre.
Like I said at the start though, you will almost certainly find differing views here. Wayne is a figure who falls into the 'love him or hate him' category for many and his style was often the antithesis of that which we all enjoy in spaghettis. If you are not a fan of the 'classic' style of american western he is unlikely to be your cup of tea.