Not only is your Sun in 1st House, but your Sun is Conjunct AC. This is a very powerful aspect if you want to make a strong first impression on others. Although this is good, your Moon is Square AC. Moon square AC means that you portray emotions to others that you do not wish to portray. An example would be this:
You are having an excellent day; you are happy with life. Out of nowhere someone may come up to you and ask you what is wrong. You will be confused by this because they had not read your emotions clearly. This goes for any other emotion. People may view you as angry, when you're not. People may view you was happy, when you're not. This square is only something you must work with, but it can be worked with to improve the way you portray emotions to others.
Most astrologers will tell you that you have a strong presence to others because your Sun sign is in it's luminary ruler. Leo is ruled by the Sun, which therefore gives you a strong presence because your Sun is in Leo. The aspects to your AC are more important than the placement of your Sun. Because your AC is conjunct Sun, you have no problem proving that your presence is very strong.
I have Sun, Moon, Venus, Mars, Uranus, Neptune, and Fortune in 1st House. My Sun does not conjunct my AC, but my Moon conjuncts AC. This means that my emotions have a strong presence in first impressions/appearance. Compared to you, my emotions are strong. Compared to me, your vital energy is strong.