This subject is really polarizing. I've enjoyed my share of TB product, and Jack in the Box, too. But Del Taco's flavor is off to me (and their bean burritos are strangely dry, require a lot of salsa ((which is also off to me)). Anyway, I don't like anything but ground beef, and the best is at Ojeda's in Dallas. There appears to be a little finely chopped potato in there, which keeps the beef really wet, without a trace of grease. No cheese even needed, or sour cream. I like sour cream with refried beans, but not with beef. Oh, TB used to have a nice chili cheese burrito, anyone remember that? And the fried burritos at Jack in the Box and Carl's Junior?
But getting back to tacos, I remember that my Mom had one of those presses to make corn tortillas at home. And the results were interesting, but not my favorite. I really like a VERY thin, delicate hard shell, that's hard to do at home. If you try making your own shells, they are liable to be rather thick, and kind of chewy, which is sometimes OK, maybe it depends on the oil you use, I don't know. But here's an idea... I used to make really thin pasta with one of those manual machines. Anyone tried that for corn tortillas? Well, if you are buying factory made hard shells, I would point out that putting them in the oven for a few minutes is a really good idea. This works well for chips that are going stale, too. Revives them.
Now, on the filling, I know my Mom must have used the Lawry's, or some other packaged item, which was OK, but I agree with the idea of just adding your own chili powder (which is almost free here in LA), and I happen to be fond of cumin (which is a little expensive), and huge bags of these two items are available at restaurant supply houses, or any latino grocery. I have read a lot of recipes for chili that call for both onion powder and garlic powder. I guess this might be an OK idea, have not tried it. At least those are pretty cheap, and you can always have them in the pantry. Also, I would add black pepper. I think I would use red leaf lettuce rather than iceberg, just chop from the end near the stem for more crispness. I don't use tomato in tacos. As for cheese, plain old cheddar is fine with me. With regard to salsa, I like it thin, runny, red, and hot. Not chunky. In LA, at the latino groceries, there's an amazing variety to choose from, most of them are pretty cheap, so you can test them out and decide which ones you like. There are basically three hot sauces: Mexican (habanero is the most extreme version, it comes in different colors, all hot), Louisiana (Tabasco, and others), and some very popular Asian brand. Now, I like roasting my own serranos. I'll post a separate item about that.