Just a short suggestion, but Holism is often taken as the opposite to reductionism, but I'm not sure if it is fully applicable in this physics example. That complex systems and their emergent properties are considered irreducible is often a characteristic of holistic approaches, in the sense that higher level processes cannot be understood by only studying their constituent parts.
However, in your first example ("from statistical physics to particle physics") you seem to be aiming for an approach that start at a macroscopic level, but then tries to find the underlying "laws", which implies reducibility. In that case, Holism isn't a suitable term. Actually, the approach you are describing is more similar to first identifying empirical/phenomenological patterns and then trying to recreate these patters using bottom-up reductionist models, which is a pretty common approach to science (simultaneously looking at macroscopic patterns and trying to explain these using lower-level mechanistic models).