Very complex questions....
I have a Scorpius Mercury in a 3D square to Neptune, this Mercury is angular. The sign of my mercury is Sagittarius, the constelation is Scorpius [shared constelation with venus]. I read the planet first as angular, then I read it's hard aspects and partile aspects [partile with Mars, Square with Neptune].
Neptune applies a sense of fantasy to mercury. It also adds in some form of mental imbalance [one so deep set that it doesn't effect my life]. Mars aspecting Mercury in a Mars place (the constelation of Scorpius is undoublty Martial) creates a "double down" of Mars energy expressed through my communication and thought. I am vastly creative and I act on it. I am a day dreamer and night thinker. I am vulgar, raunchy, sexual, and unfiltered, sometimes even impulsive. With mercury being one of my most angular planets the connections it has are more expressive in me. So when we see personal planets attached to outers, we have to assess if the planets are expresive (angular) or strong (aspect a luminary), and go from there.
Each planet must be individually looked at, as there is no all encompassing key to view all at once. Personal planets very chart to chart, Pluto is a personal planet in my chart, where as the Moon may be a little harder/less used/outer in my life.
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To understand the second question we must know what each outer planet means.
Pluto- the big bang. Instant death and instant life. Volitle search for unbiased self authenticity through isolation and reflection.
Uranus- child birth. Everything that is loud and colorful. Breathing space and room to stretch. Freedom through putting all the cards on the table.
Neptune- reading Alice and Wonderland. Realising that in some way shape or form that the book and story is real because it came from someone's mind, and thoughts are real. Making your own reality through your mind.
Apply these to the core values of the other celestial bodies to create a summary. I would only look at hard and partile aspects to begin with.
