Lore-friendly rogue-hybrid builds for Astarion?

Hey I'm new to the game, level 5, still on Act 1. My party is Sorc Tav, Light Cleric Shadowheart, Battlemaster Lae'zel and Evocation Wizard Gale, so these are the classes I've gotten to know.

I'm switching Gale with Astarion, and I've never really used Rogue. Now, looking at the level progression and the general opinion, Rogue falls behind after level 5.

I want to keep Astarion as a rogue but I don't see him as 100% sneaky, so I'm thinking a hybrid approach would be fitting.

• I definitely want to try to Gloomstaker/Assassin/Fighter build, or rather Gloomstalker/Thief/Fighter build because I favor sustained reliability over first turn burst. But this build doesn't come into full effect until later on so at level 5 I'd be a pure ranger, but I want to experience Astarion in melee for a bit before that.

• Thief/fighter comes with Heavy Armor and I really don't see Astarion wearing heavy armor. I guess wearing Medium/Light Armor still makes sense since you benefit from DEX? Still, I am not sure about this one, since I already have Lae'zel. I guess I just don't know well how this build works.

• Sword bard. I definitely want to try this build since it feels like Bard fits Astarion perfectly, but does it even add points to Rogue? I'd like to experience Rogue a bit, at least partially in a multiclass build.

• Monk, I've seen some OP Open Hand builds but I'm not sure I see Astarion as an OH monk. Also, not sure if this build has points in Rogue. Shadow Monk makes more sense, but I've heard apparently it'd be redundant to add points to Rogue.

Anything else cool for Astarion?