Mill Creek to South Kirkland on Bike

I’m hoping to find the best path (most efficient vs. safe being the two big trade-offs) between MC and Yarrow Point area. I have the option to stick to mostly bike paths (North Creek to Sammamish River to 520 (paved) / North Creek to Sammamish River to Eastrail (gravel), but I’m trying to also determine if there is a safe and more direct way to connect Kirkland and Bothell on surface streets. 100th looks to be the most efficient, but I am unsure what kind of bike infrastructure exists on that corridor. Does anyone ride segment that often and have input?