over the years I've used many many things and combinations of things... I've had good years and bad. bottom line is that there are so many factors from diet, environment, type of flea/tick, frequency of exposure, etc.
what I always come back to is using commercial/chemical products if I see fleas and need immediate action...and natural products to prevent fleas/ticks and I only change the system if it's broken - not by recommendation, new products or trends.
last spring my flea allergy dog began one of his itch/bite fests... I gave him an oral flea med right away and bathed all the animals in the house. (I believe my cat brought them in when she got locked outside once), the next month I gave my other dog a topical, the next month an oral with the allergy dog and that was it for the year. they all get springtime bug off garlic tabs and no bugs - even with constant exposure. I will warn however that garlic belches are horrid!! ha
oh, ps, you'll be glad to hear that my best years ever were when my dogs were on a predominately raw diet
no additional treatment necessary but it may be noteworthy that they also swam almost daily.