This sounds like Spinoza's pantheism, which is interesting because the spirituality of that system is famously ambiguous. "God" turns out to be synonymous with "nature." That kind of mysticism isn't as subversive as the Eastern formulations.
The only difference between this monism and scientific naturalism is that the mystic says the underlying Source is "spirit" or "consciousness" rather than some bizarre elements of matter.
Either way, there's a big difference between Spinoza's blessedness, which is the realization that everything has its place in eternity, given the God's eye view, and mystical asceticism, the withdrawal from a relatively false reality out of deference to a hidden one that subverts conventional expectations and pastimes.
The former kind is less subversive or profound, because it tries to have it both ways. That kind of pantheism can be coopted by unspiritual agendas. If everything is an expression of the underlying Self, then everything is fated and is good just as it is, including rape and murder and so forth. So this mysticism would have no moral implications except for the reassurance that everything is as it's supposed to be, objectively speaking.
In any case, I don't see much sense in saying there's only one kind of mysticism. Hinduism isn't the same as Buddhism, for example, nor is either the same as cosmicism. What makes a viewpoint "mystical," as far as I can tell, is that it's based on direct experience of a profound but hidden, often overlooked truth. Mysticism therefore entails the esoteric-exoteric distinction.