Tostada de Pescado | Photo by Nikki Buchanan   I’ve never actually counted, but I’m going to hazard a guess that metro Phoenix has more Mexican seafood restaurants than American-style seafood restaurants, which is a plus if you’re more interested in great, reasonably priced seafood than, say, la-di-da décor. El Heroico Guaymas, which opened in Peoria last December, is the newest of these no-frills, no-BS spots and based on a terrific lunch I had there...