Well that's off topic greybread. Are you aware about this?
OP you said:
Are there any aspects or placements in a natal chart that are supposed to signal this?
Traditionally, Mars is a star which indicates force, wars, plunderings, screams, violence, whoring, the loss of property, banishment,
exile, alienation from parents, capture, the deaths of wives, abortions, love affairs, marriages, the
loss of goods, lies, vain hopes, strong-armed robbery, banditry, looting, quarrels among friends, anger,
fighting, verbal abuse, hatreds, lawsuits.
http://www.csus.edu/indiv/r/rileymt/...s%20entire.pdf
This following link are useful for basic understanding of this subject:
http://www.skyscript.co.uk/marsatt.html
It's even more true in nativity's traits when Mars is operating in the Angular houses, especially within 3° from any angles in the horoscope.
Like the kinds of people who have the kind of power you can almost feel in the room, a kind of presence, and the resilience that keeps them going from one failure after another yet still succeeding at life?
It's more positive trait from Mars however keep in mind that Mars is a malefic planet. It's even more malefic when they happend to be in noon birth time [diurnal] nativity, thus making hard for every nativity to handle such an malefic in any specifics house which it's impacts generated by Mars.
My thoughts from research are.
1. Mars in 10th house.
Correct.
2. A lot of aspects to the Sun or a well placed Sun.
3. Aspects between Mars and Saturn.
This depending whether both stars are in positive aspects [trine and sextile] or negative aspects [square and opposition] and any conjunction is automatically negative because Mars is malefic star.
Generally though it's good when malefic stars operate in Cadent houses because the negative aspects of malefic stars will be impacting upon others. That's all from Hermetic view.
Don't forget too to identifying it's sign and houseruler because you can see where they will be playing out in your life. Domiciled of Mars is Aries and Scorpio and am sure you know about this. Hopefully this could help you to understand it.