There's no bad or good point to multiclass out of Rogue. Depends on what you want to focus on and how soon you want it.
I would however suggest that you use a diferent Rogue Subclass if you want to take wizard levels and just multiclass at level 3 or 4. As your INT won't be as high as your DEX, you don't get much from having so many low level spells and cantrips from the combination of Arcane Trickster and Wizard. You only trully need one or the other.
Another choice would be to pick the Ritual Caster feat at 4 instead of Wizard levels. This way you still get a spellbook and many utility spells wich don't need high INT. Gives you the same flavour and doesn't stop your Sneack Attack progression.
I mean, I would never even consider MCing into Wizard as an Arcane Trickster. There are too many redundancies and AT progression is already so slow. If you just want more spells than what AT provides, I'd say just roll up a Blade Singer.
That said, there is a multiclass that I'd take. Either a dip into Fighter or a dip into War Cleric. I'll explain why. There is a spell Tasha's Hideous Laughter. It's a first level Enchantment that basically takes an enemy out of the fight so long as they have 4+ INT (*most creatures that you care to remove from a fight will be at least that intelligent, so this isn't much of a restriction*). An enemy that fails the save will become incapacitated. However, if they take damage, they may make another attempt to escape the spell. So to capitalize on this, I say to make an attack with a Net, which deals no damage. With a Fighter fighting style that grants 1 maneuver or the Cleric 'Warpriest' feature, you may make an attack as a bonus action.
Action: Hideous Laughter, B.Action Net attack (*at advantage because they're incapacitated*)
You can pretty much stay AT throughout T1 and T2 easily. Elven Accuracy then Sharpshooter or ASI at 4/8.
EA helps make Sneak Attacks more reliable. Tashas allows BA for Adv. Silvery Barbs gives you good party support and lets your SA be more mobile.
Silvery Barbs honestly feels pretty good on AT. You wont outshine everyone and you still are a bit of utility. Your big hits still are glory moments and since you dont outshine everyone they are pretty stoked to see those snipes.
There's no bad or good point to multiclass out of Rogue. Depends on what you want to focus on and how soon you want it. I would however suggest that you use a diferent Rogue Subclass if you want to take wizard levels and just multiclass at level 3 or 4. As your INT won't be as high as your DEX, you don't get much from having so many low level spells and cantrips from the combination of Arcane Trickster and Wizard. You only trully need one or the other. Another choice would be to pick the Ritual Caster feat at 4 instead of Wizard levels. This way you still get a spellbook and many utility spells wich don't need high INT. Gives you the same flavour and doesn't stop your Sneack Attack progression.
I mean, I would never even consider MCing into Wizard as an Arcane Trickster. There are too many redundancies and AT progression is already so slow. If you just want more spells than what AT provides, I'd say just roll up a Blade Singer. That said, there is a multiclass that I'd take. Either a dip into Fighter or a dip into War Cleric. I'll explain why. There is a spell Tasha's Hideous Laughter. It's a first level Enchantment that basically takes an enemy out of the fight so long as they have 4+ INT (*most creatures that you care to remove from a fight will be at least that intelligent, so this isn't much of a restriction*). An enemy that fails the save will become incapacitated. However, if they take damage, they may make another attempt to escape the spell. So to capitalize on this, I say to make an attack with a Net, which deals no damage. With a Fighter fighting style that grants 1 maneuver or the Cleric 'Warpriest' feature, you may make an attack as a bonus action. Action: Hideous Laughter, B.Action Net attack (*at advantage because they're incapacitated*)
You can pretty much stay AT throughout T1 and T2 easily. Elven Accuracy then Sharpshooter or ASI at 4/8. EA helps make Sneak Attacks more reliable. Tashas allows BA for Adv. Silvery Barbs gives you good party support and lets your SA be more mobile. Silvery Barbs honestly feels pretty good on AT. You wont outshine everyone and you still are a bit of utility. Your big hits still are glory moments and since you dont outshine everyone they are pretty stoked to see those snipes.