Srimati Radharani's position as the Queen of Vrindavana.

All living entities are sakti-tattva (included in all the living and non-living energies of Krsna) however, there are different categories. 

To start with, basically there are only two types of living entities, Visnu-tattva, who has 60 of Krsna's 64 qualities, which is 93.75%, and jiva-tattva (jiva-souls) who have 50 of Krsna's 64 qualities, which is 78.125%. 

Srila Prabhupada – “In the Padma Purana, wherein it is said that there are two kinds of spiritual entities; one is called the jiva (jiva-tattva or jiva-souls), and the other is called the Supreme Lord (Visnu-tattva)." (87th Ch of Krsna Book, Prayers by the Personified Vedas)

There is also Siva-tattva however, he is neither Visnu-tattva (God) or jiva-tattva (jiva-soul). He is in a league  of his own and has 55 of Krsna's 64 qualities which is 85.938% of Krsna's attributes.

Srimati Radharani's position is always difficult to understand because Radharani is in her own unique mysterious category always fully absorb in thinking of Kṛṣṇa. 

To experience the loving affection of a woman, Krsna divided Himself into two and became "Radha and Krsna" the Divine Couple. 

Radharani represents Krsna's internal "sakti" potency or energy and is non-different from Krsna. 

Srimati Radharani is the internal energy, the jiva-souls are the marginal energy.

Srila Prabhupada - "Regarding your question about our relationship with Srimati Radharani, She is the internal energy, we are marginal energy. Marginal means sometimes internal, sometimes external. When we are under the internal energy, that is our normal life, and when we are under the external energy, that is our abnormal life. Therefore, we are called marginal energy; we can be either this way or that way. But being qualitatively one with the purusa, our tendency is to remain in the internal energy. Being in the external energy is our artificial attempt." (Letter to Lilavati - Allston, Mass 25 April, 1969)

Radharani is NOT jiva-tattva (jiva-soul), therefore, going by the above quote from Padma Purāṇa, Radharani is no different from Krsna and is Visnu-tattva, she is no different than Kṛṣṇa created by Him so He could experience loving reciprocal exchanges and emotions with a women.

In vaniquotes it is explained that Radharani represents Krsna's internal energy or potency and is in the combination called "Visnu-sakti-tattva." 

Srila Prabhupada - "Tattva is manifested in different ways

1 - Viṣṇu-tattva, 

2 - Viṣṇu-"śakti"-tattva,

3 - jīva-tattva, like that." (Lecture on SB 6.2.7 - Vrndavana, Sep 10, 1975)

These three words visnu-"sakti," tattva" refers to Radharani being simultaneously Krsna's internal energy (sakti) and Krsna's direct expansion (Visnu-tattva). And furthermore, when Krsna and Radharani combine in the one Body, that one Body is Lord Caitanya Mahaprabhu.

As said above, "sakti" means the different categories of "energies" of Krsna, the variety of living entities and non-living (matter) as Srila Prabhupada explains. 

Srila Prabhupāda - "Sakti means “energy.” There are many types of energies of the Supreme Lord, and all of them are auspicious. Brahmā, Viṣṇu and Maheśvara are called guṇa-avatāras, or incarnations of material qualities. 

In the material world we compare these different incarnations from different angles of vision, but since all of them are expansions of the supreme auspicious, all of them are auspicious, although sometimes we consider one quality of nature to be higher or lower than another. The mode of ignorance, or tamo-guṇa, is considered very much lower than the others, but in the higher sense it is also auspicious. 

The example may be given herein that the government has both an educational department and criminal department. An outsider may consider the criminal department inauspicious, but from the government’s point of view it is as important as the education department, and therefore the government finances both departments equally, without discrimination." (SB Canto 4 Ch 6 text 43 Purport)

Srila Prabhupada - "Tattva is manifested in different ways: Viṣṇu-tattva, Viṣṇu-śakti-tattva, jīva-tattva, like that." (Lecture on SB 6.2.7 - Vrndavana, Sept 10, 1975)

As said above, "Sakti" means the different categories of "energies" of Krsna, living and non-living (matter) as Srila Prabhupada explains. 

Srila Prabhupāda - "Sakti means “energy.” There are many types of energies of the Supreme Lord, and all of them are auspicious. Brahmā, Viṣṇu and Maheśvara are called guṇa-avatāras, or incarnations of material qualities. In the material world we compare these different incarnations from different angles of vision, but since all of them are expansions of the supreme auspicious, all of them are auspicious, although sometimes we consider one quality of nature to be higher or lower than another. The mode of ignorance, or tamo-guṇa, is considered very much lower than the others, but in the higher sense it is also auspicious. The example may be given herein that the government has both an educational department and criminal department. An outsider may consider the criminal department inauspicious, but from the government’s point of view it is as important as the education department, and therefore the government finances both departments equally, without discrimination." (SB Canto 4 Ch 6 text 43 Purport)

Srila Prabhupada - "Everyone is trying to love Krsna, but Krsna is trying to love somebody. Now how great She is. Just try to understand. Everyone, the whole world, the whole universe, all living entities, they are trying to love Krsna, krsna-prema. 

Lord Caitanya describes, prema-pumartho mahan. And Rupa Gosvami described that ‘You are distributing krsna-prema.’ So krsna-prema is so valuable, but Krsna is after Radharani. Just see how Radharani is great. Just try to understand the greatness of Radharani. Therefore She is so great, and we have to offer our respect." (Lecture, Aug 30, 1968)

Srila Prabhupāda - "Without energy, there is no meaning to the energetic, and without the energetic there is no meaning to the energy. Similarly, without Radha there is no meaning to Krsna and without Krsna there is no meaning to Radha. Because of this, the Vaisnava philosophy first of all pays obeisances to and worships the internal pleasure potency of the Supreme Lord. Thus the Lord and His potency are always referred to as Radha-Krsna." (CC, Introduction)

Srila Prabhupāda  - “Lord Krsna’s Pleasure Potency is called Hladini, so this spiritual energy of Krsna’s pleasure potency, Hladini, is Srimati Radharani Who is always increasing the transcendental pleasure of Krsna by Her super-excellent loving devotional service.” (Letter, March 29, 1970)

Srila Prabhupada - "Krsna is the energetic, and Radharani is the energy. Just like energy and energetic, you cannot separate. Fire and the heat you cannot separate. Wherever there is fire there is heat, and wherever there is heat there is fire. Similarly, wherever there is Krsna there is Radha. And wherever there is Radha there is Krsna. They are inseparable." (Lecture, Aug 30, 1968).*×*.