In my belief, God can be an entity or an object, but is in no way confined to or defined
by that concept!
Whatever representation of the Divine Consciousness resonates with me personally (Mahadeva), is the conduit through which transcendence can be actualised. I understand that saying "God is not a thing/being" also places human limitations, restrictions and conditions upon an omnipotent presence...in that God
can be a thing IF God wanted to appear as such. In Hinduism, this is called Ishwara (Easwara) or the Ishta Dewata.
As for "nothingness"...I prefer the term "everything-ness" or even the Buddhist term Tathātā or Such-ness, where everything just is because it is and for no other reason. The terms "nothingness" and "void" just sound too cold, impersonal and off-putting for me personally and would not be conducive with a motive for starting a spiritual practice....especially for a newbie or anybody who has problems doing something just for the sake of doing it..because that usually comes as the
result of meditation, rather than being a necessary prerequisite for it.
However, there are many ways of approaching the crux of the Eternal...from Vedanta, to Bhakti Yoga to the Sāṃkhya schools of thought (which I personally subscribe to):
https://en.m.wikipedia.org/wiki/Samkhya
The Sāṃkhya school is a strongly dualist one and the main proponent of it was Patanjali who codified Yoga into His Yoga Sutras/Aphorisms which propounded the concept of "Ishwara Pranidhana" or "Surrender to God" - having the ability to bypass/subdue the ego through surrender to something beyond or greater than what the ego is and "nothing" seems to nullify the whole point of doing that.
These are just my own thoughts and experiences based upon my chosen path..others will have different ones and in no way am I saying this is conclusive ...it is just what I have chosen to believe and follow..