Fresh locally-grown ingredients are a must because local growers grow vine-ripened different varieties than those in the supermarkets thatare picked green and ripened in gas chambers. Cilantro gives it authenticity.
A huge variable that most people miss is the fresh garlic; it makes a big difference what variety you use. Applegate is so mild it is almost bland (Your wife will love it in pesto) but Red Toch has a rich mellow garlickiness with little or no bite. Inchelium Red and Persian Star are true medium flavor and medium pungency (hotness) for all-around use. If you want real musky, earthy garlickiness and a hotness to sear the mouth, select a Rocambole like Spanish Roja or Killarney Red or long storing Porcelain garlic like German White or the hottest one of the bunch, the Habanaro of garlic, Romanian Red.
If you want to impress the world with a truly distinctive salsa, don't just use any old garlic, get the one that really makes a bold statement and defines who you are and shows the world that you are a man to be reckoned with.
Make it a pleasure for a delicate palate or an trial by fire to be endured only by the hardiest; the choice is yours if you grow gourmet garlics in your own garden.