Hmm..
...difficult one to answer as what is 'good' for my taste buds might not be same for you.
Personally I don't mind sweetness as then I don't need to add anything to sweeten my sauces...and just like Galina said..splash of vinegar will give some balance to the flavours.
When I make my own sauce, I always aim to use as much as possible more 'meatier' type of tomatoes..or 'cooking' tomatoes, as they are less watery. But also add some cherry ones or other sweeter sort just because their flavours.
One nice 'meatier' type is Jersey Devil that I like for sauce making..good cropper too!