Very interesting, Irina. First, let me say how much I enjoy these outfits. Love the green with the ecru or white in #1, the proportions (and the white hits) in #2, and the coat/ hat/ shoes (which do look awfully close?) in #3.
Re complements -- I do, and I don't use them, if that makes sense. For this tonal experiment that I am trying, I am endeavouring (where I can) to as Hannah P suggested in the video Sarah DB linked to -- match bag and footwear if the clothing is monochrome and a textural near-match, or use a neutral version of the colour in a tonal outfit. Just to see how I feel about that.
But of course I can't do it consistently -- I just don't have the items in my closet. And some of the time it just doesn't feel right to me anyway.
Typically, my bag and footwear don't match, although Jenni's absolutely right. --- I do use my footwear and/ bag to "bookend" my hair (or other aspects of my outfit) in an attempt to create cohesion. For footwear, I use white, ivory/ecru, grey, and silver to bookend my hair. All of these work really well for me, and I do it summer and winter.
I would argue that you have "bookended" in #2, not literally (because it's not your head and your feet), but you've still ensured there is a balance of lights and darks on the top and bottom of the outfit with white showing at cuffs, collar, and shirt bottom as well as the shoes. This creates harmony and cohesion and makes it feel intentional.
Looking at my Finds—the accessories I use in winter —you can see that it is possible for me to do a complement in silver (if a grey hat or just my hair counts as silver?), in red, and in blue. But in reality, I tend to mix it up -- use one colour bag and another footwear. The scarf is usually patterned, so it's tied in to one or the other or to something else in my outfit.
I will have to pay more attention to whether people are bookending or matching in my town. I'm not sure they are! But I see so few people dressing in anything other than gear around where I live. I'll be in Vancouver next week -- I'm going to pay attention to the streetscape there.