Does the many not intuitively suggest a one at the top, or that the many are aspects of the same?
Those are two different propositions. I do agree with the former, and that's what Neoplatonism proposes. All things emanate from an absolute, ineffable, simple Monad. But the key thing is, the Monad is not a god, it is not a conscious, acting, personal entity. Rather, as Proclus concludes, the gods are the active, individual manifold of Henads, by which all things participate in oneness. The gods are each
a One, even if they are not
The One. Some modern philosophers in that school, like Edward Butler, go even further, and proposes that the gods are each The One individually.
The latter proposal, though, I don't agree with. There were polytheistic philosophies that proposed such-- both Stoicism and Middle Platonism said that all gods are contained with the Logos, who is Zeus; earlier Neoplatonists like Plotinus were ambiguous about where the gods fall within the chain of being. But, as I mentioned, later Neoplatonists like Proclus and Damascius concluded differently, and their systematic theology positioned the gods at the same ontological register as The One.
Though it should be noted that a lot of other pagan philosophers did not conclude there was a logical reduction to a singular mover or cause. Epicureanism, for example, was vigorously materialist and hard-polytheistic, in a way that can only be characterised as poly-deism.
If one's concept is of a deity/god/entity that has no beginning, for example, Occam would suggest a singular rather than multiple, surely?
If
a god can have no beginning or end, there's no reason that
many gods can't exist with such quality. Occam assumed monotheism an
d constructed his argument to suit what he already believed. When applied to the peculiar character of a prime mover, it is a non sequitur to say that there
must be only one mover.
Does paganism even contemplate the eternal?
Quite a lot, actually. Christian thought derives from Middle Platonism, primarily. But by that point, Pagan philosophers had been contemplating the nature of the cosmos for over six centuries. Eleatic philosophers arrived already at the notion of an eternal, unchanging quality behind all things; the later Platonic idea of the Monad derived in large part from
) since you only took it because you don't have that belief. And yes, Pascal was not suggesting "fake it until you make it" type approach, but rather "practice puts you in a better disposition toward finding belief". But, still, that's begging a whole heap, and doesn't even touch, as you suggest, on the nature of God. Does God even care if you believe as long as you lead what he considers a good life? Is he petty in that regard, etc? Some might say that it's the test, that He's put everything you need in front of you to recognise Him, and if you don't, well, oops, sorry, no harp-recital for you. But the best I can muster is the Gallic shrug. 
