You haven't given any reason why implicit initialization of variables is better than explicit. Explicit initialization is already required for any initial value except 0 and it conveys intention. It's not onerous -- it's 3 extra characters, and it makes it clear that you meant it to be zero (and you didn't just forget to initialize it).

I think the case for omitting "= 0" is weak at best. If you encourage this style some novice/intermediate programmer could do the same thing for a stack variable, which will bite him/her. Given all these costs/downsides, what is the benefit of not typing those three characters?