When I say “the gandhabba that has lost his body (died)”, I am referring that the physical body died, not the gandhabba.
I know the gandhabba is who sees, hears, etc. with the pasada rupa of each sense hitting the hadaya vatthu, and citta vithi arising from hadaya vatthu as a response. The body is, as you say, just a shell controlled by the gandhabba. The brain computes and sends the sense inputs to the corresponding pasada rupa, hits the hadaya vatthu, from hadaya vatthu arises a citta vithi containing javana citta, and those will be interpreted and executed by the brain.
I know that the gandhabba, freed from a dense body (human/animal body), has more capabilities for seeing and hearing, including seen without light, earing without air, and at large distances, but is not able to touch and smell. Being joined with a dense body, I am not sure why (I’ll ask in another thread), the gandhabba has his capabilities inhibited, not being now able to see and hear at distance, and now depends on the physical body sense inputs and the brain.
Now, the doubt was the following. If the gandhabba, out of the body, has more capabilities (except for touching, savoring, and smelling), is his memory also more potent than inside the body?
Your last statement is “The gandhabba may not remember previous lives in different physical bodies.” I am not sure if you mean that the gandhabba may no remember previous lives while inside in different physical bodies, or even free from a physical body it may not remember previous lives it had in previous physical bodies.
I know that inside a body a normal gandhabba is not capable of remembering things beyond its physical life. But once the physical body dies, will the gandhabba, now free from the physical body, be capable of remembering things of all its actual bhava, not only its last physical life?