10 levels wont even be enough for much multiclass potential yet, would need 20 to make it more viable.
In my PnP games, we almost NEVER reach over levels 8-9 and we multiclass sometimes nonetheless. Multiclassing is viable before level 10.
Due to the rigid rule that you need 4 levels in a single class to get the Feat or Ability gain, experienced players often do 4/4.
But, Warlock level 2, can be a viable addition to a character for example.