I will start.
Firstly, I came to KM from Alfred as I was always intrigued by what KM can offer that Alfred couldn't. After some time I realised that KM really complements every single application that I use on my Mac. It enhances my workflow but above all it gave me the freedom to really think in a new way. It allowed me to manage complexity and different workflows of each application by allowing me to make my own macros with KM's standard library of macros that is immensely powerful. Together with Karabiner, I now operate every single application from my keyboard. I have extended my library to include so much that I would really love to share with you some of the things I managed to achieve to make with KM thanks to this wonderful community and this amazing tool built by @peternlewis.
I love to structure my things. I group macros by their function and scope and I love prefixes. (a: for app specific, g: for general, p: for play).
As an automation tool, at first I found creating macros for specific groups took too much time (clicking through things is annoying). Fortunately this community has a lot of really smart automation applescript wizards. One of them is @DanThomas. He created a couple really neat meta macros for KM editor itself. The two things I missed the most were added by him. I can now search for any group from KM and go into it from a launcher interface as well as go to any macro I have in KM from same interface :
This was really huge and eased up my experimenting and quick prototyping of KM macros, editing of them, adding new ones and so on. He also created an amazing macro of favouriting actions users most often use. These three macros are essentially KM ver 8 for me already.
As you could probably see, all of my macros had prefixed added to the name of the macro with the scope of the macro (which app or group macro belongs too). This is intentional and I use it to sometimes search through and run macros from Alfred workflow.
As well as of course searching for macros to go to from KM editor itself from one of Dan's macros. Problem I had though was writing out these prefixes on my own every time. Life is too short for that. So again with amazing help from this community I was able to make this macro that does just that for me.
Here is the macro for it. And preview of it :
How awesome. Now KM can be consider a proper automation IDE. With great search for action hotkey :
I could do everything and do it fast. So here is what I did that changed my workflow the most and what I use KM mostly.
Search by Image. Wow. In some apps you simply can't get to everything using hotkeys and you are forced to use the trackpad which I very much dislike. This can often be avoided by using find my image macro. For example Hazel doesn't have any hotkeys in the app. If you want to create a new rule, you have to use your mouse. Well this can be avoided by simply doing this :
Here are all the hazel macros that I use. I hope sharing these macros like this works. Tell me if it doesn't. 
I started using this search by image functionality more and more as I bring more and more actions away from trackpad and map it my keyboard which has enormous freedom and efficient thanks to Karabiner.
My most used case of KM is most certainly as an application switcher.
This alone saves me probably hours a months from switching between apps. The cool thing about it is that I map an action that will both open and switch between that app on the same hotkey. I press and hold w key and press k and Safari opens. I do this again, and switch from Safari to previous app. I can't tell you how amazing it feels to operate my system now and I have a lot of apps.
I also use KM for some string manipulation. Macros like these :
Simple but so very useful.
KM also has macros that trigger on application launching. I use this macro in this context as I type in both Russian and English and I never need Russian when I am using the shell.
Here is one awesome macro that I use multiple times a day. It gives me an url of a link that Safari currently has open :
And here is another one that was made thanks to @ccstone and @JMichaelTX. It opens first / second / third link from google from a hotkey.
I use it all the time now and it saves me another countless hours from my life. I still didn't figure out how to transfer the script to work in youtube, reddit but I will get there.
I also love clicking various buttons from a hotkey. I see what most often buttons I click on the web and add them to my macro like so :
Will need to improve this using a switch statement as @peternlewis suggested but for now this works and I love it.
So yeah these are my most used macros that I use in KM. I really want to thank this community for helping me solve my little problems and bare with my newness to this whole thing of programming and making things happen with code. I appreciate you help. @Tom @DanThomas @ccstone @JMichaelTX @MitchellModel and every one else. The awesome thing is that this all just the beginning and as time passes more and more Alfred workflows, KM macros will be added to my arsenal. How awesome is that?
So I hope some found this post interesting and insightful. I consider myself a heavy user transferring into the realm of making my own tools and applications to help solve problems with software that I and hope few other people have. I want to ask anyone who read this to comment with something similar on how do you guys use KM to solve your problems. I love workflows and would love to hear yours.
Thank you guys. p.s. this was long 
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