As we know there are 7 shuddha and 5 vikut swar total 12 and signs in zodiac are also 12.
The sun rules Leo and moon Cancer, only one sign allotted to them, remaining 10 signs distributed to five planets.
Gemini and Virgo to Mercury,
Taurus and Libra to Venus,
Aries and Scorpio to Mars,
Sagittarius and Pisces to Jupiter,
Capricorn and Aquarius to Saturn,

Sa and Pa are always shuddh. Sa Shadaj is the main swar from where all swars can generate so it is the Sun (Leo)base of solar system, then Pa Pancham is Moon (Cancer), the sun and moon are never retrograde and both have only one sign. Some times Moon may be invisible so some Ragas are without Pancham (pancham varjya).
Re Rishabh—Budha Mercury lord of Gemini(Suddha) and Virgo (Komal)
Ga Gandhar-Shukra Venus lord of Taurus(Komal) and Libra (shuddha)
Ma Madhyam-Mangal Mars lord of Aries (Shuddha) and Scorpio (Tivra)
Dha Dhaivat-Guru Jupiter lord of Sagittarius (Shuddha) and Pisces(Komal)
Ni Nishad—Shani Saturn lord of Capricorn (Komal) and Aquarius (Shuddha)

I have tried to understand the effects but never made experiments on large scale because I am not a doctor and I have no resources for that.

I would like to say my experience. In my birth chart moon lord of 6th house is in 8th and in malefic aspect. My favorite Raga is Brindabani Sarang with both Nishad(Shani) and without Gandhar(Shukra),because Venus is Badhak and situated in Marak Bhav and Saturn Lagnesh aspect Lagna and favorably placed from moon,it puts me in higher/spiritual level and fillings of divine love, all fear and anxiety disappears and it gives me strength. Raga Malhar(Miyaki) with both Nishad also put me in deep séance of Shant Bhav and filling like meditation.

One more experience, a grand old man very good astrologer and classical music lover suffering from asthma every now and then I suggest him to listen/(Gungunana) meditate on the Swars of Bhupali, his response was good, though asthma was there but filling of relief he was enjoying, his Sun in Gemini afflicted by Rahu and Mercury lord of Gemini (lungs) also afflicted by Saturn(Nishad)but in good aspect of Jupiter(Dhaivat) so I sagest Bhupali(Nishad Varjya) and he felt better.