@anand,
Let me put forward my perspective, which may be wonky, never the less, here it goes…
Patanjali’s Raj Yog and Kapila’s Sankhya both do not lay much emphasis on Prana, especially Sankhya. Though, Raj Yog talks about pranayama, but it is dealt with a broad brush, unlike Hatha Yogies. Further, Sankhya does not use the term Chitta but only Manas, where as Patanjali uses both rather interchangeably.
Now as per Sankhya, on which the Raj Yog is said to base with few exceptions, says that except Purusha (self, jivatma), Pradhana (Prakriti) and all other tattawas, which are derivatives of Pradhana, are jada, including Mahat (buddhi), manas and ahemkara. The three gunas (Rajas, Sattawic and Tamasic) are the attributes of Pradhana and not Purusha.
The aim of a yogi is to train with specified techniques (Maha Yog, may be one of them) so that Pradhana with which Purusha identifies Itself, withdraws like a nartaki (dancer) who goes back stage after finishing her performance. Once Purusha identifies Itself to be separate from Pradhana and its Jada tattawas, one is free from the bondage.
I understand from your post that to be in tamsic guna is inappropriate. I may like to rely again on Sankhya, Tamasic is also restraining. These three gunas work tighter like wick, oil and fire, though having different attributes; they support each for the same goal. One is always in the state of a mix of all these gunas; one of these may be predominant, though. The idea of any yog is to go beyond these gunas.
During sleep, depending on the type of dream, you may be in a mix of different gunas and not always tamsic as you state. During dreamless, deep sleep, one is in turiya state which is beyond any guna.
Indriyas are always outgoing but perception is made only when manas connects with one or more of them (like being in a class room and still not being there). The manas also simultaneously connects with Chitta, which is the store house of all your experiences (including your previous births but is password protected, you come to know of it only when agaya chakra is properly simulated) and impressions (sanskaras) (Chitta, in idle state, like home page will go to that experience which is deep rooted like sex for a sex maniac),
It also connects with Buddhi and ahemkara at once ( Yudhistra in Maha Bharata when asked by yaksha as to what it which is fastest. He replied- ‘manas’. It is faster than speed of light or particle entanglement).
Buddhi determines as per your experiences (and wisdom and knowledge)
Ego aka ahankara is self assertion:- All that is considered(alochita) and reasoned(Mata) refers to me, in that I am competent, all these of senses are for my sake only, this does not concern anyone else, hence I am.
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Now everything starts with manas, drop it and you become only drasta, a stage beyond any guna.
Hatha yogies realised the potential of prana, They wanted to enhance life span beyond 100 years so that in only one birth they realise their own self and be free from bondages. And hence the processes of asanas and prayanams were devised to control flow of prana to various body parts through nadies to nourish them.
I agree prana may be utilised gainfully for self healing and enhancing life span but it in no way can destroy the karmic seed as you say. Karmic burden has to be endured.
Sorry for a long banter
