It does get awkward - in my experience players will often have their characters use spells during social situations, like the earlier tongues example, or guidance, and you don't always want things to immediately erupt into conflict as a result.To me the initiative system is an abstract solution to who gets to go first. It doesn't need to follow what is happening in the narrative but it does need to exist to allow for different narrative options.
If someone cast Charm Person and it failed then it stands to reason the target would be upset and might fight.
But that's not what I'm asking.
Does a fight happen before the Charm Person is cast? The initiative system allows for an enemy to attack before the PC does a hostile action and vice versa. If a PC is going to cast Fireball I instead call for initiative and if someone beats their initiative then it gets explained away such as 'they see the intent in your eyes before you can act'.
My option would be that if someone's casting something that's disadvantageous to the subject, they can make a Deception check versus either the target's passive insight if the target wasn't paying direct attention to them, or as an opposed check if they're actively interacting. If the target fails, they're considered to be surprised for the first combat round and we can skip straight to resolving the spellcasting attempt. If their Insight check succeeds, we go to initiative.
I know it's been ruled differently officially, but I run suggestion as the verbal component being the suggestion itself, i.e. "I suggest you head home and take a rest, you're not looking well." It's the Jedi mind trick, and even when Ben Kenobi is only convincing one officer that these aren't the droids he's looking for, he can do so without alerting the other troopers that something weird's going on - unless the officer succeeds on his saving throw.The question then is whether the game needs to account for that with enchantment spells? If I cast Suggestion on a knight to ask them to give their horse to the first beggar they see can that knight win initiative and strike me down before I talk? Or put another way do we want that opportunity supported in the fiction?
For me I want to allow a space for enchantments and to me that means they can happen before initiative is rolled in the right circumstances. That makes them powerful but otherwise they would be too weak.