Need help on audible system

Questions regarding audibles: Is the concept of checking plays at the LOs "overrated"? I know there are many teams that check successfully all the time, and we use checks at the LOS as well. But some times I feel it would be better to run a "bad" play and execute it really well than to get to the LOS and make the kids think extra about what they now have to do. About as complex we have ever gone with audibles is "check with me" and call two plays in the huddle. (Or that week everyone knows that Power and toss are paired for example. So we come to the Los and see they took one of those away we run the other play. I have found checking plays versus some teams is a total waste of time b/c they stem so much before the snap.

Also a question for coaches who use words to call plays and not numbers: How do you indicate which direction a play goes when checking at the LOS? For example a word we might use for veer is Houton if running left, and Cougars if running left. We could also use something like Vancouver or Vermont. For the passing game we use hand signals and cue words.