[monroewalker]

Karabiner has already been mentioned here but I'll add that goku (https://github.com/yqrashawn/GokuRakuJoudo) is THE way to setup Karabiner and it can be hard to overcome the extremely verbose and unergonomic default json config of Karabiner otherwise. Goku also makes it trivial to add shortcuts which are activated by quickly pressing one key while another is held. I use this for the kind of launch mode described in the OP. eg. w + e = editor (Intellij), w + r = chrome, w + f = firefox.. The drawback to these shortcuts is that they can unintentionally be activated when regularly typing since we don't always release a key before pressing the next. That's only happened seldomly for me though since "w" isn't a frequently used letter and I've set the shortcut activation window pretty low so the w + <key> key has to be pressed essentially immediately after w.

Similarly, I use q + w for previous tab, q + e for next tab, and s+d to open the clipboard history from Alfred