When I'm trying to connect a branch, I follow any leads I can find, in any direction, because I never know what's going to be the profile that finally connects that branch to the main tree. So I go back as far as I can, but when I hit a brick wall (which usually doesn't take me very long), I go sideways: add siblings, and siblings' spouses, and then siblings' spouses' parents, and however far I have to got to make the connection. At least once I've made the connection and orphan that branch, I've given WikiTree that much more "surface area" for other people to connect their branches to.
On my own family, even though I got my branch connected, I still work out in all directions, looking for still more connections. (And, sometimes, finding unconnected branches which then end up being connected through mine.)