An Eclectic Collection of Fun and Effective Builds 3

[Amnestic]

Starlight☆Duelist

Someone who takes centre stage, always clamouring for the spotlight...and also stabs people.

Race: Any really, though half-elf is preferred for it's 4x stat boosts and double skills.
Ability Scores preference: Dex>Cha>Con>Wis>Strength>Int.
If you're a half elf you should be able to start with 10/16/14/8/12/16 as your stats, which works out just fine.

Weapon of Choice: Rapier or scimitar, maybe a Longsword if you can get your DM to agree to it being Finesse when one-handed.

With Half-Elf, Bard, and Backgrounds we're flushed for choice, but Athletics+Acrobatics+Performance are all key to the narrative of the build, along with one or all of the other 'face' skills. Taking another racial option will knock two of them out, but if you've got any left over, grab Insight and/or Sleight of Hand.

We are neither intelligent nor particularly wise, and you're going to be relying on other people for spotting monsters, but that's fine! Once you do see them you'll be sure to take centre stage.

Level Progression:
Levels 1-6: Bard. We're going Swords at 3rd, our ASI is spent in Dex. We go to 6th for Extra Attack, but nabbing the short rest refresh on BI is also important.
For spells, we're ideally not using stuff that takes up our Action (which we're using to stab people), so Healing Word/Silvery Barbs/Heat Metal/Kinetic Jaunt/Mass Healing Word are great choices, with some longer duration buffs (eg. Aid) to throw up outside of combat. We're not spelllcasting as a general rule, so stuff that relies on your save DC to be really effective? Give it a miss, if you can.

Bard Expertise goes into Performance and Acrobatics.

Levels 7-9: Rogue 1-3, into Swashbuckler. Gets us Cha to Initiative, helps us fight our enemies duelist-style, nets us a total of 2d6 Sneak Attack per turn, and gives us more stuff to use our Bonus Action on when we're burning all our BI on flourishes.

Rogue Expertise goes into Athletics and a face skill (Intimidation is probably most narratively appropriate, but deception works too).

Levels 10-17: Back into Bard 7-14, going all the way up to 14th for 'free' Flourishes every turn, letting us dump our Bardic Inspiration back into other people. ASIs go into Dex (maxing it out) and then Con. 16 Cha is going to be what we started with, and what we finish with for the rest of our career.
Though I said we want to mostly be using non-action battle spells, I will shout out Otto's Irresistible Dance here: For the concept, it's mandatory.

For Magical Secrets, Spirit Guardians, Holy Weapon (only if there's no paladin in the party - don't steal their thunder before they get a chance to use it!), Armour of Agathys and Flame Shield are all choices to consider, since you're on the frontline. Guardian of Nature (Great Tree Form) is also pretty good since it nets you con-save advantage and advantage on your finesse weapon attacks...but being all bark-y and leaf-y isn't very thematically appropriate, so probably skill this one!

Levels 18-20: Rogue 4-6. ASI into Con again for a bit more resilience, since we're on the frontline.

Expertise batch #3 goes into either other face-skills, or Insight, or Thieves Tools in the unusual event that you're in tier 4 and still need to pick locks (or disarm traps that other people have spotted for you).

Feats: None
Final stat breakdown (on a half-elf): 10/20/18/8/12/16
Final level breakdown: Bard (Swords) 14/Rogue (Swashbuckler) 6.

With a 7th level spell, two attacks a turn, flourishes, 3d6 sneak attack, and six skills with expertise in them you're a pretty solid all-rounder. You won't dominate at dealing damage or casting spells or even being a skill monkey, but you do a pretty good job of all three of those all the same. The build also works at every level. It never needs a moment to 'come together'.

If you want to play a more Duet-y character, Swashbuckler can be exchanged for Mastermind instead. Both fit the concept in different ways, but my preference is Swashbuckler since there can be only one who stands at Position Zero.

Addendum: You can take a Hexblade level at basically any point in this build (though I'd usually advise you do so at 1st, 2nd, or 7th) in exchange for a rogue level, which lets you stack charisma instead of dex, and stick with medium armour. This is marginally better for your spellcasting, bardic inspiration, and nets you shield proficiency, though worse in other ways (dex saves/skills, mostly, since you still get cha to initiative from swashbuckler). I don't like hexblade dips though, so I say go away to them!