Sir,
As per my understanding any path which includes worship/ propitiation of Shakti is classified as Tantra. Although it is too wide and broad a classification.
No Sir, then what about Vishnu Tantra, Shaiva Tantras which are large in numbers and Budhist Tantra which are so large in numbers .. in fact Vajrayana is wholly tantric in its basics, orientation and practice .. there are great tantrik names there like sages Nagarjuna, Tilopa, etc etc.
The schools which revolve around worships of Shakti are called Shakta ( as against Shaiv or Shavites)
but all shakta schools are not tantrik. for example Devi Mahtamya of Markandeya purana genrally called as Durga shaptashati may be tantrik or non - tantric or Viashanavite. Godess Tara in Budhism or Padamavati under Jainism may or may not be tantric.
Tantra has a philosophy, basic cosmology, and ontology which when followed makes the path tantric and the essence of that power of letters and mantra.
From what I understand Vama-marga translates to Left Hand Path.
Vam Marga is a philosophy in itself and has its own ontology and beliefs. However generally it revolves around worship of Das Mahavidyas with ultimate worship of Mahakali ( Vam marg) or Rajrajeshwari Tripura Sunadari ( generally Dakshina marg). Even there worship of Mahavidyas can be carried out by Dakshina marga or Vam marg. The difference is between what constitute of liberation and what will bring about emancipation and liberation. For example Shankaracharya worshipping Tripurasunadri differs from Vam marga in philosophy and essence and in basically and ultimately being different in the mantra. Reading Soundarya Lahiri etc would explain it.....
it results in differentiation of stages and methods of attaining nearness of the God or Goddess.
However, you obviously are much more qualified to explain, would request you to please to enlighten.
No sir, the subject is too deep to be knowledgeable. I am just a theoretician.
From my understanding intoxicants play a pivotal role in vama marga.
The aim of Tantra is to detoxify the body and mind from all impurities, illusions and untruth and lead the mind to the truth and realisation which is the true path of liberation of the soul and merging it with the ultimate soul / Shakti.... so the use of intoxicants may or may not be recommended therein.. Generally Shakti puja may involve many rituals but ultimate aims is related to awakening of the primordial power called Kundalini..
No path including those of the great saints is untouched by the great philosophy of tantra .... tantra literally meaning a vehicle or a machine or a web of power centres and is but only a means and not the end.
