Marron is the only child of Android 18 and Krillin. She's shy, sweet, and quiet. She doesn't appear to possess any fighting ability unlike her parents, but she is very loyal and loving.
Pros: 
Marron is yet another offspring of a Z team pairing. Krillin is the strongest human and Android 18 is a strong warrior capable of masking power and existence since her "ki" is unreadable. Pairing Trunks with Marron would unite saiyan power with unpredictable, potentially hidden and lethal human/android skills by bonding the Briefs family with this one even if Marron isn't a fighter.
Marron's loyalty and dedication would bring a "motherly" aspect to their marriage. Many males tend to seek out "motherly" types reminiscent of their own. Trunks is a momma's boy. He'd feel comfortable and nurtured in this relationship. Marron would be that typical wife, ready to come to the aid of her husband's needs and desires.
Marron's sweetness and dependence would bring out the protective nature in Trunks. Trunks would know it would be up to him to defend and protect his family and home. This may also bring out a need for him to train a bit more thus increasing his saiyan and warrior abilities.
Marron's age is relatively close to Trunks. She's roughly five years younger than him. That's just enough to add youth and vigor to the relationship while allowing for maturity at the same time.
Cons:
Marron's mother, 18 has been shown to be very interested in money and attempts to acquire it any which way she can. This may influence her daughter as well. Trunks has a LOT of money. Ever devoted to her family, Marron may seek Trunks out for this alone. Success in nabbing him would make her mother very proud of her. She'd be just like all the other females out to use him.
Marron's father, Krillin has shown his ability to "suck up" to the stronger fighters in the group, particularly saiyans. This could be a desire to assure protection for himself and his family, especially since all the enemies they'd ever faced outclassed regular human fighters regardless of their strength and ability. Krillin too, may nudge his daugther towards a saiyan husband and what better than to have a super saiyan who's also got a fortune?
If Marron were to be the wife of Trunks,
the saiyan race loses another potential chance to increase and
save itself (eventhough, genetically speaking, it's already lost).
Each pairing of a saiyan or half-saiyan with a regular human diminshes
the
saiyan bloodline by half of what it was.
Marron is very passive. Trunks would likely be forced to be the dominant figure at work and at home. While most men could live with this set-up, Trunks' personality reveals that he'd probably not fare well as such. He needs a strong female. He's grown up all around strong females, particularly his mother, his best friend Goten's mother and was babysat by Videl, Goten's brother's wife. A passive, dependent female may catch him in unfamiliar territory and create strain and stress on him and his family. Trunks has enough of that from work, adding family to that could push him over the edge mentally.
What would marriage be like with these two?
This would be one of those typical
white-picket fence, life in the 'urbs type family. Marron would
likely be the mother and housewife while hubby Trunks goes to
work. He'll come home to already made meals and a wife willing
to please him and allow him to relax after a hard day's work.
Love may exist between these two, but they could end up with hidden desires. Trunks will desire a stronger female who'd challenge his authority while Marron seeks only his paychecks. Marron would find it difficult to fend off aggressive females who also show interest in her fine catch of a husband. The tension of these possibilties could lead them to divorce, in which case, Marron would likely win and take a good chunk of Trunks' assets.
Then again, love may grow on them and they could end up "happily ever after."
What would a kid from this pairing be like?
A kid from this pairing would likely be one of those cute, adorable, cuddly, "awwwww" type kids. They'd be sweet, mannerly, and respectful to their elders. Then again, the kid will also be a quarter saiyan. This means it could be trouble in the making and a potential brat. No matter the outcome, Trunks and Marron would make good parents.
My takes on this pairing?
I'm indifferent about this pairing. One minute I can see it and the next I can't. Marron's devotion and sweetness clashes with her money-hungry potential. Perhaps I can't decide about this pairing because Marron is such a minor character in the Dragon Ball series. We hardly see her and when we do, she's more background then any sort of character. We don't know a whole lot about her personality, life, and so forth so it's difficult to deduce how she and Trunks would get along let alone if there's any chance of a future between them.
NOTE: The Trunks/Marron image was created by someone and I'd like to get solid permission to use it (I stored it for personal viewing on my harddrive some time ago). I don't know who did it,but I'd love to credit them and their site, etc. If that person or anyone who knows them could let me know, it'd be most helpful. Thanks.