I'm gonna stick with Nexus line as long as devs will develop for nexus phones,
cause I just cannot use Android phones without Slimrom and on nexuses it fits in the best way,
so never settle! :silly:
Finally, I found pretty much easy solution of how to add "clear all recent" button.
So, to get this awesome button you need just a few simple apps: Tasker, Repetitouch, Custom Notification.
After you are installed all those apps, you good to go ...
I would be glad to see "clear all" button in recent or get any mod which will bring it back.