The only fully effective and kind way to train dogs is with clicker and treats. there is no "too treat heavy based training"
Clicker training is for training - you do not have to use the clicker once the dog has learnt a behaviour. However you will have found a really easy way to teach a dog to do anything once it is clicker savvy.
This is not a stealth boast but a 12 week old puppy that has been clicker trained should easily be able to sit, down, stay, wait, recall, paw, high five, spin, twist, roll over, leave it and touch, watch me etc no trouble at all. Clicker training is quick, fun and effective.
However you may have gone to a rubbish class - not normal to have clients leaving in tears 
look at the Kiko puppy videos and see if they help you to see the benefit of clicker training. If you have kids they usually are greaaaat at clicker training.
It is a new skill so takes a bit of getting used to (Not much) very simple click the correct behaviour and treat! But once you get it you will be hooked and the have the best trained dog around.
kikopup you tube