Part I: Gaps along the hardwood floors

Not sure how to deal with this problem. There are wide gaps along the exterior walls of the house that open directly to the crawlspace below. While I plan to cover them with some quarter-round, it seems that additional backing to the gaps will help with energy efficiency and keeping those giant, flying tree roaches out, which can easily squeeze through tiny cracks (experienced this when one tried to crawl out of my shower head, *shivers*)

The gap along the wall in the sleeping porch

For now, until I finish sanding the floors, masking tape is a makeshift solution:

The gap along the back wall of the kitchen. The stink bugs like to visit through this one.

Part II: Filling the Gaps in the Baseboards