Isis is generally not regarded has having become the major deity we know of today until fairly late. This is after she absorbed many of the aspects of earlier deities that were major in oldest periods of ancient Egyptian history. These deities include Satet, Sopdet and Hathor. She is often regarded highly among ancient goddesses because her worship eventually became widespread outside of Egypt. Her fame is also due to the Greeks who built the well known temple devoted to her in Aswan at Philae. In her earliest forms, she was the personification of the throne of Egypt, which some would call a reflection of the matriarchal nature of Egyptian kingship.
Horus and Seth were among the oldest dieties worshipped in Upper Egypt at places like Nekhen (horus) and Naqada/Nubt/Ombos (Set). Horus in the earliest forms was a sign of kingship and victory over one's enemies. This is a very early archetype of winged victory or divine provenance where the hawk is symbolic of having supreme vision and vigilance over the movements and activities of one's enemies. It also represents divine presence and consciousness on the earthly plane with a conscious presence both in the day(waking) and the evening(sleeping) state.