It's an order of magnitude easier to befriend crows in the city, as opposed to the country. The more rural you are located, the more time it will take you to befriend a crow.
The first one is the hardest. They'll start bringing friends, eventually. They like they rituals and consistency -- you've already discovered this. They also lose interest if you don't keep it up regularly.
Don't look straight at crows, they don't like it at all. When they're ready to be your friend, they'll put themselves into your field of vision. I was able to communicate vocally with crows and get them to respond before they were comfortable being face-to-face friends with me.
My mother had been feeding birds for a while. The local crows quickly realized that she's a soft-touch, so they sit on the garden fence outside her window. If she sees them, she throws something to them. It started with one female bird who eventually brought her young. She would take treats and feed them to her annoyingly loud offspring before eventually having something for herself. My mother got a kick out of this. The matriarch would eventually come to her window and tap on it. But if my mother looked at her directly she'd fly back to the fence. But she could open the window "nonchalantly" and throw treats without scaring her off as long as she didn't look straight at her. Other crows have noticed this. She now has a dozen or so hanging around. The original bird sits looking into her bedroom window in the morning waiting for her to get out of bed, and then flies around to the kitchen to tap on it. You see, there's competition now.
The first one is the hardest. They'll start bringing friends, eventually. They like they rituals and consistency -- you've already discovered this. They also lose interest if you don't keep it up regularly.
Don't look straight at crows, they don't like it at all. When they're ready to be your friend, they'll put themselves into your field of vision. I was able to communicate vocally with crows and get them to respond before they were comfortable being face-to-face friends with me.