I see more than one wishing in the Feedback Tracker that iClone would load faster. 
So I added this detail there and share it here too.

Here's my workaround solution.
Uninstall iClone then immediately reinstall it. Software, patch, bonus packs, etc. Not 3DX

It worked twice for me so far.
It went from taking 70 second to being ready to use down to 7 seconds.
If you look at the task manager iClone would just not be active 0% resources for a good 20 seconds to basically almost no resources used.
When you click on the splash screen the spinner spins for a good 10 seconds before you can use it.
Immediate uninstall/reinstall fixes the lag issue