If I had to guess what the next FotM would be, I'd guess Rogue + Booming Blade combos, doubling up on cantrip damage and sneak attack, while not losing out on extra attacks like most other weapon classes do.
I like to play a Rogue. As a tank. With a whip.
Sure it needs a few levels of barbarian for protection but it works.
I actually have a build that encompasses both of these points. I call it my Belmont Battlebuckler, and it's fully AL legal.
VHuman Folk Hero (swap Animal Handling & vehicle proficiency for Perception & language)
Stats: Str 10 Dex 16 Con 14 Int 8 Wis 12 Cha 14
Fighter 1/Swashbuckler Rogue 4/Battle Master Fighter 3/Rogue 17
ASI/Feats: Magic Initiate (Racial, Booming Blade, Blade Ward, Hex), Spell Sniper (4th, Green Flame Blade), +4 Dex (8th,10th), Martial Adept (12th), +2 Con (16th)
Fighting Style: Dueling/Defense (depends on preference of +2 damage or hitting AC 20)
Maneuvers: Trip Attack, Sweeping Attack, Riposte, Pushing Attack (MA), Disarming Attack (MA)
Skills/Tools: Athletics(Fighter/Expertise), Acrobatics(Fighter/Expertise), Insight(Racial), Perception (Background/Expertise), Stealth (Rogue), Survival (Background), Thieves' Tools (Rogue), Woodcarver's Tools (Background), Cartographer's Tools (Battle Master)
Languages: Common, Infernal, Abyssal
Gear: Studded Leather, Shield, Whip
Strategy: Sneak Attack + Maneuvers + BB/GFB for optimal DPR output. Add Hex if necessary. Spell Sniper extends range of BB/GFB to 10', allowing for them to be used with the full reach of the whip. Action Surge is for emergency Dodge/Blade Ward use.