Best way to "bridge" neighboring faces/ add geometry?

[realSuperglue]

Hello!
I have 2 probably related questions/ scenarios:

1) I get that Wings3D is extrusion or volume based, sort of. Now I want to connect the selected vertices in the following picture:

What would be the best/ a good way to go about this?
Currently I'm extruding the 3 faces inbetween, then delete/ collapse edges until I'm there. Not the best workflow IMO.

2) How do I bridge 2 neighboring faces, for example in the following situation:?

That gets quite messy (rendering "errors") when I delete edges and vertices here and there until I'm allowed to connect the vertices at the bottom.

Thanks in advance.