You know how your using microsoft word, and you type something wrong, it lists suggestions on the fly for what word to spell? How about 2 things which would be AWESOME for everyone.
1) Have something where you make a change and if it's too drastic a popup says be careful this could kill your engine
2) Have something where you put your mods in, it makes a tune for you, and then you fine tune it from there. I know the coding would be a PITA but would make a great product PHENOMENAL!!!