The awoos of the Barghest

While I'm talking about dogs, I think the howling of dogs breaking someone out of a vampiric trance is unique to Stoker; protagonists in other stories tend to be aided by the power of God (Marquis d'Urfe in The Family of the Vourdalak is snapped out of his trance by the cross necklace he wears digging into his flesh, while Hedwig is protected from Kostaki's trance by a blessed palm frond dipped in holy water). Jonathan being helped by the dogs parallels another Stoker work, the short story "The Judge's House", in which the protagonist is aided by the rats living in the titular house, which attempt to ring a bell in the house in order to signal for help. It's an adorable recurring motif.

The passage about the dawn makes me think of this one from Varney the Vampire:

What wonderfully different impressions and feelings, with regard to the same circumstances, come across the mind in the broad, clear, and beautiful light of day to what haunt the imagination, and often render the judgment almost incapable of action, when the heavy shadow of night is upon all things. There must be a downright physical reason for this effect—it is so remarkable and so universal. It seems that the sun’s rays so completely alter and modify the constitution of the atmosphere, that it produces, as we inhale it, a wonderfully different effect upon the nerves of the human subject.

Rymer being Rymer, he naturally has to insist that this is a physical, scientific phenomenon.

Vampires being discovered asleep in their tombs is actually fairly common, although generally the process of discovery is not quite so perilous as Jonathan's. Sometimes (as with Sigismund, Clarimonde, Clara Crofton, and Har (in "Manor")), the location of the vampire's grave is a known fact. Other times (Carmilla and After Ninety Years), discovering where the vampire is buried is a whole process. Generally, the vampire is defenseless in the daytime; Dracula's hate-filled gaze that (spoilers for Dracula Daily) causes Jonathan to fumble his shovel swing is something of an innovation. The closest we see to this in another vampire story is Kostaki in The Pale Lady, although this instance technically occurs before he rises as a vampire:

The corpse’s eyes opened and stared at me, more alive than I had ever seen them, and, as if the two rays they emitted had been palpable, I felt what seemed like two red-hot irons plunging into my heart.

It's not the only instance of an evil-eye type power in a vampire work prior to Dracula, but it's the only one (that I know of) that occurs while the vampire is dead/asleep.

...No, wait, I tell a lie. It's in Varney, sort of.

"The deed was done; there was sufficient light for us to look upon the features of the dying man. Ghastly and terrific they glared upon us; while the glazed eyes, as they were upturned to the bright sky, seemed appealing to Heaven for vengeance against us, for having done the deed. "Many a day and many an hour since at all times and all seasons, I have seen those eyes, with the glaze of death upon them, following me, and gloating over the misery they had the power to make. I think I see them now." "Indeed!" "Yes; look—look—see how they glare upon me—with what a fixed and frightful stare the bloodshot pupils keep their place—there, there! oh! save me from such a visitation again. It is too horrible. I dare not—I cannot endure it; and yet why do you gaze at me with such an aspect, dread visitant? You know that it was not my hand that did the deed—who laid you low. You know that not to me are you able to lay the heavy charge of your death!"