I'm running out of pan space but I want at least one more pan. I want cast iron but asking advise whether to get regular, flat bottom or grille type. I live in an apartment and don't have access to cooking outdoors. I want a cast iron for hambugers, grilled vegetables as well as hashed brown potatoes. I have a Calphalon stainless steel for these now but think I'd get better results with cast iron.