IMO there is no need for multi-classing. Between backgrounds, sub-classes and ASI hybrids are freely available.
Mind you, my background here is BG1/2, or early DnD editions in general.
E.g. why Warrior-Mage if there is Eldrtich Knight? Why Cleric-Rogue if Trickster Domain and Criminal/Street Urchin background?
Etc. etc. ...
I would like Paladins to be Warrior-Clerics, serving specific Deities.
Thats why Multiclassing is for! You can dip into cleric for your deity choice.
