A College of Swords Bard with 3 levels in Warlock will be great since you'll be able to wear medium armor with 14 DEX for max AC bonus and use CHA for your weapon attack and damage using Pact of the Blade, giving you lots of skill points to funnel into the attributes you want. The addition of Hex to your arsenal will also pair well with Flourishes for respectable damage output. You're not going to match the potential of a Fighter but you'll have a whole ton of utility, and extra short rest to recharge your warlock spell slots, and be very tanky when needed. Plus you get Expertise and Jack of All Trades for those dice rolls.
