Hi, is it bad to add redundant tags? Although they may be redundant to people editing in Michigan, is it not better to be explicit so the router will know it is legal to bike on sidewalks? 
I can start adding smoothness and ensuring width is present as well to improve routing (as sidewalks usually have inferior smoothness to roads, but not always, as streets can sometimes have more debris present than sidewalks [side note: is there a way to tag the smoothness of a bike lane separate from the road, for example when the road is smooth but the bike lane accumulates debris from the road?]). 

I was trying to primarily focus on adding bicycle=yes on sidewalks adjacent to one-way and especially busy/fast roads like Saginaw and Oakland to fix routing where an unnecessary (and oftentimes dangerous, as it usually means riding with traffic on a de facto 45 mph road) detour would be suggested simply to avoid using the sidewalk. 

I can understand the concerns about the dangers of high speed biking on sidewalks, but I would think that should be something that the router should account for when seeing the width and the combination foot/bicycle=yes. Although I think sidewalks should ideally have separate bike areas added whenever possible to make traffic safer for all road users, but obviously that's not an OSM issue.

As for bicycle=yes on roads, should it just be left up to the router whether that road can be biked? Should I only add a bicycle tag when it is bicycle=no, such as on segregated freeways? 

I've also been tagging roads explicitly with their foot tag, whether yes or no, because that depends on factors not related to tags on the roadway itself, but instead to whether there is an adjacent sidewalk or not. Is that okay? Should I just leave the tag blank on roads with sidewalks and only explicitly add foot=yes on roads without sidewalks?

I've also wondered about places where access is legal but hardly practical, such as on roads where there is no gutter area separate from traffic lanes (see the North Larch St Bridge from Lake Lansing Road to East Cesar E. Chavez Avenue and vice versa [I do now see that you marked this as cycleway:right=no. Is this sufficient to tell a router that this is not a good way to route?]).

Thank you,
Aenet