Swashbuckler/Bladesinger?

[RickAllison]

I would love some help from the community on this one. Backstory: I began the campaign with a Swashbuckler, intending him to simply be war-scarred, yet attempting to be normal and jovial Aarakocra (he had one relapse where he tried kill two party members, but he is better now). He was haunted by what he perceived to be his failure that led to his entire company perishing in the war with the Elemental Plane of Earth. Third session in, the DM decides that his BBEG is actually responsible for this (I was not fond of this plot twist, as it doesn't seem to make any sense, but I digress). The end result is that my old character left the party as he now is hell-bent on murdering this scrying sonuva*****. I would like to continue his level development as he goes on in case he has reason to come back (possibly with a legion of furious denizens of the Elemental Plane of Air...), and so I would like input on the title potential multi-class.

He will have learned the art of Bladesinging from another possible PC I'm designing who is a more traditional Bladesinger, so the restriction to (half) elves is accounted for, but it is the viability I'm concerned with. He is already a Swashbuckler 6, so what combination of that and Bladesinger would be best? Rogue 6/Wizard 14 for the bonus damage from Int, Rogue 18/Wizard 2 to just get the basic spells and the bonus to AC? A combination with other classes to make up for the hole I've already dug myself into? Thank you.

EDIT: I should note his stats as well. He rolled 8/16/15/14/15/14 (already nice!), which with his Aarakocra bonuses and the ASI from L4 has Str 8, Dex 20, Con 15, Int 14, Wis 16, and Cha 14. He is very liberal with magic items, so I could also come back with a Headband of Intellect to have Int 19, as well as potentially several other uncommon magic items or a rare.

[CaptAl]

Swashbuckler/Bladesinger works quite well IMO. I feel like +Int to weapon damage is kinda weak, though. At that point you'd be WIZARD/rogue and far less likely to be in melee. I would say grab 6 levels of BS for extra attack and a couple haste spells a day then place all your remaining levels in rogue.

That would give you a solid defensive upgrade (bladesong and blur or haste), coupled with a solid offensive upgrade (extra chances to land sneak attack/possible SCAG cantrips), excellent utility (ritual caster and 3rd level spells), plus all the rogueish defensive and offensive goodies.

With haste active you can booming blade a baddie, use your haste action for the attack action which in turn activates your two-weapon fighting 2nd attack, then skip/fly away possibly drawing the bonus damage or causing the baddie to waste his action.

I wouldn't go higher than 7/8 levels in BS this way, though. Song of Defense competes for your defensive reaction, and +Int to weapon strikes is close to even with the 3/4d6 sneak attack you loose going heavy bladesinger, but only if you never miss.

TL/DR; Swashbuckler 14/Bladesinger 6 is better for a melee two-weapon highly mobile skirmisher.

[RickAllison]

Thanks, that's fantastic input!