I actually use mouser's Launchbar Commander as my perfect portable USB launcher, and it's great. On my flash drive root directory, I have a link to LBC's exe that uses a relative path so it will launch under any drive letter (wasn't easy to do). Then it's launched, and I have all my portable apps organized into nice categories. I access using the icon in the tray or by using a hotkey which will pop up the menu under my mouse. It's a really great solution.
As for programs, I use mostly small utilities that are already available as portable installs (like XYPlorer). I use some programs from PortableApps also. I don't use any pre-made portable suites, and I don't use any specific portable launchers. For launching, LBC is the best, so why would I try to use anything else just because it's a portable thing now? Thanks to mouser for building that into LBC.
Screenshots of my setup are below:
The tray icons
Note: I use USB Safely Remove on computers I use a lot to automatically run LBC as soon as the USB is inserted.
I hope that is useful.