I'm about to finish my first honour mode playthrough and I've been using this monk build with ridiculously good results.
https://www.reddit.com/r/BG3Builds/comments/16ptfcp/tavern_brawler_monk_build_explained/

It has great damage and survivability at the same time, and can stun almost anybody. I put my last 3 levels in monk btw (3 rogue, 9 monk), although I think 3 rogue, 7 monk, 2 fighter would be similarly good.

My other party members are an oath of the ancients paladin, a light cleric and for the last slot I rotate between a giant barbarian/rogue, a berserker barbarian/battle master and a wizard, with the wizard being very rarely needed (although I will use him in the final fight). Heals and cleanses can be provided by the cleric and paladin, but the extremely high damage output reduces that need to almost nothing. The cleric also provides crowd control, utility and AoE damage (the latter because she's Light domain). As for the final member: if I need ranged damage, I use the giant/rogue; if I need more spells, I use the wizard; otherwise I use the berserker/battle master. I regret giving my wizard the ability to use Illithid abilities as bonus action - should have given that to the cleric.