Suggestions for continuing my multiclass after level 5? (Using the 5e spells mod)

This build uses the 5e spells mod (https://www.nexusmods.com/baldursgate3/mods/125). Importantly this means I have access to green flame blade and booming blade.

I spent the first 5 levels getting the minimum requirement to fulfill my dream for the character. Specifically I knew I wanted:

• A build focussing on green flame blade and booming blade as my “no resource” basic attacks.
• Dex as my highest stat
• An off-hand weapon as well for bonus action attacks

So here’s what I built so far with my first 5 levels:

• Fighter 1 (armour and weapon proficiencies, two weapon fighting style, con save proficiency)
• Rogue 3 Thief (cunning action, extra bonus action, sneak attack)
• Wizard 1 (green flame blade and booming blade, and some utility and defensive spells)

I have the diadem of intellect so I have Int 17 and could focus my other stats into Dex and Con (and then Wis just for the saving throws).

What should I do next? I’m not interested in seeking out Extra attack since I want to use these melee cantrips. Should I get more rogue levels for sneak attack improvements? Or more wizard levels and maybe be an abjuration wizard?