Help me out

Can someone else look at these charts for my sister? She thinks i'm the expert astrology lol. But really i'm a self taught newbie. Here is the interpretation of the synastry I gave her.

For starts their suns conjunct and their mercuries conjuct so their essence and the way they communicate are the same. I told my sister that this is good and bad as the parts that they don't like about themselves they might not like in each other as least as far as ego and communication go. Their moons trine and I see that as good and his mars trines her moon which makes for passionate attraction . Her mars and chiron in loose conjunction to his moon. They have mars /south node double whammy so they may have battle together and might out grow each other . Her Venus is trine his Jupiter and oppose his Saturn to me it seems that he both expands and restricts her loving nature. She also hits his moon with her outter planets pluto and Neptune, she may have some level of control over him (pluto) and they may be psychically linked (Neptune).

If you attach a synastry bi-wheel you'll probably get some responses. Trying to read two separate charts is kinda tough.

The rulership of the planets must also be factored into the equation; also the 5th and 7th [axis of relationships] are important pertaining to love and marriage.
Neptune rules the 5th H, while Mars rules the 6th and Venus governs the 7H thus you would want to consider their aspects in particular. The polarity between the 1st and 7th is also important.
Given the Grand Air trine in the composite, involving the 7th H, this would appear to be an auspicious pairing initially, involving mutual growth and transformation via the influence of the other [Pluto/Mars]. This could also be a relationship with karmic undertones [ Venus/Pluto; Neptune/NN sextile Pluto]; this implies there are lessons to be learned for both which may be more apparent than for most couples, as denoted also by the trine of Jupiter. Compatibility is certainly evident given the relationship between Moon/Venus/ Mars.
Couples usually know what is good and right in their relationships, but seldom know what the conflicts are all about. Aspects of tension show what those lessons might involve. You would then investigate the interactions between:
Pluto/Saturn [also karmic in nature]; air and water can create imbalance;
Pluto rules the Ascendant, and is also square to Mercury; there can be some conflicts over power and control, as the individuals attempt to assert their own individuality and identities. They would need to avoid domineering tendencies in one or both parties. Communications can be problematic, creating misunderstandings and potential disagreements, due to their differing mind sets [opinions, attitudes].
Pluto/Libra; they must strive for equality and harmony in the relationship; the composite Sun in Capricorn shows they both want to be respected and dutiful; they must be accountable for their own actions, rather than transferring the blame onto the other partner when discord arises. Combined with the Aquarius Moon/Venus there can be emotional detachment and together they must learn to understand the purpose of emotions, which represent their rudder in life. The Moon square Uranus denotes mood changes that can contribute to instability.
Saturn with it's karmic implications, rules the third H again emphasizing the need for good communication skills and equality in terms of 'intelligence'. Saturn placed in Cancer, shows that they must work to ensure emotional balance between the two as well. Denial of the emotions creates blockages on the subconscious level, which can spill out and create problems in the relationship. The Uranian nature of the composite Moon shows that emotional detachment may be the problem, rather than too much emotional reactivity, and this can create it's own set of problems. Note also then, the opposition of Saturn/Sun in this chart, which can further contribute to issues arising relating to their individual identities, and sense of autonomy. Look also to the polarization between Neptune/Mars which can indicate deception, lies, betrayals and breeches of trust.
Remember that the composite shows the general nature of the relationship as a couple, affecting them mutually, while the individual charts would provide greater insight into their individual needs, expectations and desires. Good work on your initial analysis.