I have Mars in Leo in 11 H. I'm athletic, agile, fast 100 m sprinter in youth , long distance runner (for exercise) competitive in games and sports -love the challenge. Always preferred track and field as opposed to team sports - like to take the whole glory or fall myself. I'm not theatrical unless I'm angry. I know I have the upper hand when humiliating people in public and can outdo anyone with any measure, but hates being stood over in public and really don't like public dramas. My Mars in Leo I like. It's bringing in the Sun for me in an otherwise Virgo/Pluto/Saturn weighted natal with Virgo Sun/ASC. I can call on my Mars in Leo at any time. Go for a jog, revitalise, feel vibrant, become playful and see what the evening has in store. My Mars is fairly unaspected and stands away from my stellium, which has it's advantages.
Edit - To sum up I think Mars in Leo can be somewhat proud and aggressive but more than likely that energy is positively channeled through physical sports/excercise. I think this placement bestows me with plenty of optimism and faith in the joy of living. Me feeling depressed doesn't last long, even if i sulked and tried to. There are to many simple pleasures too cheer me up, like a glorious dawn, sunshine after rain, inspiring ethical people, a walk, a glass of red and a nice steak.
One thing I will say is that Mars in Leo is very protective, is not a fence sitter and takes sides easily and stays loyal. It is a fight to the very end - if it was physical. In a mental argument, the Leo Mars would easily give in when they can see reason, or have tremendous respect for the opponent - it's a noble defeat. On the other hand I'm the sort of mum who goes to the school yard and eyeball anyone that's given my kids grief. God help anyone that hurt the people I love...So for a quiet Virgo Sun/Asc I think I have a strong Leo Mars.
Cheers!
N