Sun aspects to the outer planets can show you your purpose and how you are going to use your core energy in this life. It will not tell you where you will devote that energy in terms of vocation or experience (though the Sun's placement in the houses might give a better clue), but it will tell you how you go about expressing your ego.
As with all things in astrology, the quality of the aspect matters. Whether it is a soft aspect (trine, sextile) or a hard one (conjunction, square, opposition) will have the most impact on both how easily your ego drive is expressed and how readily the world accepts this purpose in you.
You of course can have more than one aspect to your Sun, and in that case your personal ego drive will be more complex and expressed in different ways at different times. None of us are simple!
Below are the Sun/ Outer Planet archetypes and how they express themselves:
Sun/ Saturn aspects: Serious, Hard-working, Burdened, Self-defeating, Self-Critical, Builder, Long-suffering, Disadvantaged, Stoic, Resilient, Perfectionist, Pessimistic, Career-focused, Over-achiever, Late-Bloomer
Sun/ Uranus aspects: Rebellious, Non-conforming, Change-makers, Weirdos, Future-focused, Idealists, Humanitarians, Unpredictable, Principled, Reformers
Sun/ Pluto aspects: Intense, Powerful, Intimidating, Persevering, Perverse, Sexy, Vengeful, Over-Powering, Fighter, Violent, Victim, Personal Transformation. Destroyer, Restorer, Killer-instinct
Sun/ Neptune aspects: Ethereal, Angelic, Artistic, Supernatural, Enigmatic, Chameleon, Intuitive, Caring, Performer, Dreamer, Liar, Charlatan, Wolf in Sheep's Clothing, Psychic, Deceptive, Deceived, Healer, Mage, Truth-seer
Sun/ Jupiter aspects: Leader, Inspirational, Promoter, Popular, Generous, Religious, Zealot, Ego-centric, Provider, Wealthy, Pleasure-seeking, Lazy, Avoids Responsibilities, Robust Health, Overweight, Enthusiastic
I will tackle Natal Sun aspects to the Inner Planets in an upcoming post!