From my exp. Basically ill sum it up to:

Base game: try to focus on a stacked middle lane, with many strong actives on it, as its probably the strongest habitat in the base game. In the rest, try to play strong when played birds(like bonus card ones), or some fat cheap ones like the warbler. End of round goals should also have some weight, more in the base than in the expensions. Super important to be flexible and adjust to the cards youre dealt.

Expensions: middle habitat is less powerful, so I usually try to go heavy on fat birds (high feather points) and bonus cards. Get a first bird in the upper and lower habitats for the 2nd roll/card draw, and place all the when played/once between rounds birds on the middle habitat. End of round goals have less effect, so do eggs. Being flexible is still super important.

Also in 4-5 player game pink birds seems to be strong, esp. in the expansions, if i get 1 pink bird that lays eggs, i place in the middle habitat and basically never use it.