Is Aragorn more like King Arthur, or Alfred the Great? Of course, he does not have to be like either!
But there are zillions of people who have drawn a parallel between Aragorn and King Arthur (e.g. 288,000 Google entries pair these names!) - but I can't myself see much resemblance except that they are both Kings - and both Good Kings, at that.
The main similarity is that both were aided by a wizard - and Gandalf is (obviously) derived from Merlin; as are all modern wizards. But Gandalf and Merlin are not very alike - in particular Gandalf is much more Good than Merlin; whose main intervention was originally (in Geoffrey of Monmouth) to enable Uther to commit adultery.
And this matter of Goodness is what also distinguishes Aragorn from Arthur; because Arthur is quite flawed as both Man and King (in most versions of the story) - and his only major prowess is generalship (as a single combat fighter he is exceeded by several knights, notably Lancelot).
By contrast, we know that Aragorn is among the best Men of all time - intelligent, wise, learned, a healer, skilled at tracking, hardy, a great fighter; and possessing a will strong enough to wrest control of the Orthanc palantir from Sauron. We confidently expect he will be the same as a King.
On this basis, it is probably closer to the mark to consider Alfred the Great as a closer equivalent to Aragorn; since Alfred seems to have been both an exemplary individual; and more of an all-rounder than Arthur.
Alfred was apparently not only an inspiring leader and excellent general, but also a major administrator and lawyer; scholar and author; and a deep and devout Christian.
Alfred also has a very roughly analogous trajectory from being reduced almost to a 'ranger', hiding on the 'island' of Athelney in the Somerset boglands, before a 'return of the King' to reclaim his kingdom (about half of what is now England) from The Danes.
I don't suppose that Tolkien seriously based the character of Aragorn on any particular historical or mythical model - especially considering that Aragorn developed narratively, by increments, from a brown-skinned hobbit-in-clogs called Trotter.
But, in character, Aragorn seems more like Alfred than anyone else.