+1 for manual instrumentation should be the exception, not the norm. However many time there is instinct to log everything that you don't pay enough attention to what one metric is most valuable to your business. And when you need it, its just too tough to get it + system slows down because of logging everything (if building inhouse).

Btw Autotrack is direct competitor to heap. How are you going to maintain differentiation? Or something for which heap gives 10x that autotrack doesn't?