'God' is a dyad of Heavenly Mother and Father, they are co-creators and parents of all. The metaphysical reality is that all persons are male or female and there is no-one who is neither or both.
The whole person is therefore neither man nor woman - each being incomplete - but a dyad of the two complementary persons man and woman; sealed in an eternal loving relationship.
Traditional Christianity - for good reasons - has focused on God the Father, but the time has come for change. While we might continue to refer to 'God' as tacitly implying the two personages, this is coming to seem evasive, and even dishonest.
Of course the potential for being misunderstood, and deliberately misrepresented, is vast - it is a hazardous, dangerous doctrine; but that applies to Christianity in general - and so, where there is need, hazard does not deter.
The key fact is the grounding in the dyadic and complementary metaphysics; this is the basic assumption, which is attested by direct intuitive knowing and coherence, not by empirical 'evidence'. It is thus metaphysical assumption rooted in faith and personal knowledge which clarifies and protects the concept of Heavenly Mother.
What she is, is a matter that need attention, now.
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What she is not?... She is not the same as the Father, not another name for the Father, certainly not an equal to the Father. Complementarity means dissimilarity: two complementary things are not the same, are not equal - their quality is that both in combination are needed to make the whole, the unit.
Heavenly Mother is a part of the dyad of God - not a Goddess; she is not any kind of revival - because she has never been acknowledged nor known up to now. She is of the future, not the past.
She is nothing to do with feminism, and is indeed ultimately the opposite of feminism. She is not in any way 'for women' rather than or in preference to being for men (any more that the legitimate Queen of a nation is for the women of that nation more than the men! Or that mothers are for their daughters more than their sons. Nonsense!).
She is not a 'balance' yet not a take-over either... Heavenly Mother is a fact and a necessity.
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Heavenly Mother is a mystery - because divine; but she is a person we already know, from our long pre-mortal lives as her sons and daughters; we have known her for as long as we consciously knew anything.
If, for good reasons, we have been focused on Heavenly Father (and the reality of our Mother awaited the Mormon revelations of the middle 1800s) - then why do we need her now?
We need her now because the unilateral focus on the Father is preventing our divinely-destined spiritual progression. Where we are now (culturally, individually) is nihilism, despair and death; but we cannot (and should not) go back (which is why all attempts have failed); yet going forward is blocked by a partial and distorted understanding which cuts to the root; progression entails acknowledging the fullness of fundamental understanding, and building-upon that.
At some deep and intuitive level we know this, or we can know it - each for himself or herself - for the asking (serious asking). And we can find out more, and as much as we need, by addressing questions in prayer and meditation and listening for the responses - observing the responses.
(This is not really a matter of 'worship' because the incremental collapse of that concept is representative of the reasons why our Heavenly Mother's time has come. It is instead a matter of acknowledged reality, followed by love; and of conversation, communion, communication.)
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This is not a matter of capturing Heavenly Mother in definitions, any more than this is helpful for our Father; because persons are known, not defined.
There is no need and little value from dividing-up the powers and responsibilities of our Heavenly parents any more than our real parents - yes they are different, and rightly; but no, the difference is not a consequence of, nor captured by, legal categories.
Persons are primary; loving relations are the cohesion and source of organisation.
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How important is this - is it necessary? Since the idea of Heavenly Mother is unsafe, will be deliberately and carelessly misunderstood and misrepresented, will be a reason for hatred and loathing... is she not better set-aside, down-played, kept-quiet about?
That is a decision you need to make for yourself. You need to feel that Heavenly Mother is something we need to know - now: urgently; and which honesty requires that we know - openly, explicitly; knowledge the lack of which is poisoning us in many ways.
The impulse is there, the impulse is in our hearts and unfolding in Western culture. If the impulse is refused and kept unconscious; it will nonetheless emerge in distorted and inverted forms (like feminism, like misogyny, like resentment and competitive exploitation between men and women).
But if Heavenly Mother is acknowledged and takes her place explicitly and joyously as a completion of our knowledge of God and the basis of our mortal lives; then the destined new era of consciousness may commence.