Preface
I'm relatively new to dnd and this is my second character build so I'm still trying to understand the mechanics for different classes and how to efficiently stack them.
Character Inspiration
My build is heavily inspired by los luchadores from the movie Mutafukaz. In MFKZ, the luchadores grew up in a long lineage of hero luchadores who protect the world from evil by wrestling (Barbarian) them. But these particular luchadores have doubts because their generation hasn't ever seen any meaningful combat. So they just practice their skills and make money wrestling on TV (Bard) until their patron sends them a sign. When they finally found a sign, they had to sneak (Rogue) into a high security alien military compound to rescue a kidnapped scientist. Since my character is inspired by that movie, that led me to the following 3 classes...
Stats
At level 9 I'd have: Human Bard1/Bear Totem3/Assassin Rogue5
18STR, 15 DEX, 13CON, 9INT, 11WIS, 14CHA, 57HP, 13AC
Vicious mockery, Cure Wounds, Thunderwave (not sure I care about the other cantrips/spells)
Expertise in Athletics gets me +12 for Grapples and shoves. Stealth will probably be the other expertise.
Bardic Inspiration, +3d6 for sneak attacks, advantage during rage and assassinate, +2dmg during rage, and my meat shield combo Danger sense, Bear Totem & Uncanny Dodge.
Considerations
I should note that Im definitely not opposed to using weapons. But I'd prefer if they were either unique or smaller. For example, a whip, daggers, a net, or improvised weapons.
At level 10 Ive considered taking: Bear Totem4 for +1CON+1DEX, or buffing my attacks with Tavern Brawler or Fighter1 for the Unarmed Fighting variant.
Thoughts? Is this build a viable option in mid-high level combat? If not, is it possible do to improve my survivability without just starting from scratch?