All the icons in the world and I really didn't like any of them for an app launcher. I'm using this with the dashboard on the icons only task manager but it looks alright with the application launcher as well. I built it using the base of the Konsole terminal icon, adjusted shadows and added the little rounded blocks. Also got the padding just about right to match them in size - at least in my setup.

Others could probably do better but I wanted to try. Now my app dash, konsole, settings all look nice and neat from left to right on the taskbar. Anyway, here's the .svg if you like it.

https://cloud.s6vi.net/s/GeMrDcgoR5oKfNN