Hi again,
As an astrological chart is personal of nature, the 6th and 10th houses are 'mundanely' associated with employment and career. Yet in other terms and sense, the 10th house is associated with one's outer position and standing in life, as applied to one's 'destiny'.
The 6th house is the house of SELF service, which can refer to applying one's energies 'to work upon one's self'. This is never more appropriate than when Leo, ruled by Sun .... one's personal will and motivation in life ... is on the cusp.
A highly respected astrologer, Dane Rudhyar, called the 6th house 'the house of crisis in consciousness' because, lying between the 5th house of 'creative self' and the 7th house of 'the other', an individual is on a see-saw between putting the interests of one's self OR that of another first. This would seem to influence the double edge you mentioned regarding a Libra Sun, finding the balance between different sides..
With your interest in subjects that go beyond the 'mundane' life, looking at the houses from this perspective might provide you with a clearer understanding of the 'why' of your place and physical existence.
Whatever house system used, Pisces remains the Ascending sign, comparative to the physical constitution. Its traditional ruler is Jupiter (that I personally use when relating to influence of Moon feelings ) and modern ruler is Neptune (when relating to Sun inference ). Both planets aspect Jupiter; neither planet aspects Neptune. An active Neptune is within a square aspect to the planet of physical manifestation, Saturn. Physically a conflict between the two energies can weaken (Neptune) the skeletal and outer structure (skin) limits of the body(Saturn). Osteo conditions, immune system issues are often apparent. Mutable sign influence can refer to issues in agility and mobility.
Another house system would place Jupiter in the previous house. Yet Equal house's 6th house position would see its square to natal Mars as relevant in physical complaints and the effect upon one's 1st house constitution and 10th house career. Mars has rulership in the blood, muscles, inflammations of all kinds, and rules one general active energy. Jupiter also has rulership in the blood, body tissue, fat, and gives a general 'increase' upon everything with which it comes into contact. Positively speaking Jupiter is the planet of 'good health'. Its positive aspect to natal Sun, offering self confidence and optimism, would appear to rule out heart complaints.
Should your interest in astrology be further influenced by the Uranus opposition to undergo a change of direction, you might find the positions of the nodal axis worth while reading. The SN in Pisces in the 1st house has been observed to be relevant in those cases where physical disorders (NN Virgo) play an important role in life's progress.