Greetings. Halflings make better dex barbs than str, but you can make it work with such high stats. Stout halflings are the best for the +1 Con, although you do not seem to have a use for it. Your first feat can be Lucky, since you already have a maxxed out Str and high Con. Coupled with resistance from bear totem it will make you very durable.
The obvious flaw of this character is that he will never be able to utilise Great Weapon Master, so he will lack behind in damage compared to any other martial. And a martial without proper DPR is a gimped martial. You are still good at tanking, but without proper DPR you give no reason to the intelligent enemies to attack you. There are ways to lessen the impact of your sub par damage, either by addressing the issue directly, or by giving you versatility.
For direct damage increasing, one lvl of fighter gives you a combat style, two lvls action surge, level three maneuvers. Paladin can be interesting thanks to divine smite, less so than a Fighter for a two lvl dip though, both because of lesser benefits as well as because you will need to move stats around. Ranger also makes for a nice 3 lvl dip and deep stalker is both strong and flavorful, but honesltly the combat benefits of the class suit more a burst attacker like an assasin rogue. It can make a good dip later in your career, but at 8 lvl, barb 5 / battlemaster fighter 3 makes for a stronger character overall (or fighter 5 / barb 3, depending in what you want to progress).
An alternative could be a mix of barb and druid, removing your disadvantage from small size with wild shaping for combat and casting for utility. This is definately a Druid first build at these lvls though, you will want to go barb 1 for con saves / druid 6 for access to polar bear and giant elk (most potent combat forms of their lvl and probably the peak of moon druid strenght) / barb 2 for bear totem resistance / druid 4 for elemental wild shape. Afterwards either you go with druid for more wild-shape forms (unimpressive though) and spellcasting, or you return to barbarian or another martial that suits you for more combat prowess. Monk has great synergy in particular, especially the first lvls as you get to add your wisdom to AC. The first lvl can even be taken as early as after or before barb 2 in the example above, or even maybe at lvl2 (So at 8 lvl you are a raging bear Barb 1 / monk 1 /druid 6). Sun Soul monk gives you a way to deal with flying enemies in beast form too.
Another great bonus of the druid / barb multiclass is that ghostwise halfling becomes a top tier choice since they have a wis bonus and the ability to communicate in beast form.
EDIT: Started writing it before the posts above, the crit fishing twf style is also effective and is an as-good-as-it-gets way to add the damage you need to pull your weight. I am still not sure if I would prefer champion fighter from battelmaster though. I still consider Battlemaster optimal since one or more maneuvers at first round of combat are better than a potential big critical at the end of the fight, but overall both archetypes have their moments.