What is you defense and dodge? Is that health self buffed or raid buffed? Are you using stamina food? Do you have 3/3 in Survival of the Fittest and points in HotW and ILotP? What about armor? Not really sure what "properly spec'd" means.
As for hit/expertise, they are unnecessary but nice to have. I've raided through TK/SSC with zero or maybe 45 hit rating and zero expertise. TPS is negatively impacted but it's not a critical issue. As for the initial attack, my guess is that you're over estimating the number of misses because they are catastrophic. Try opening with faerie fire and a lacerate, works well for me. A good Kara tank should be 500-700 TPS, TK/SSC tanking you want to be up at 900-1000k TPS if at all possible. Make sure to use a steady rotation of Maul/Mangle/Lacerate with Dem Roar and FF as needed. Never miss a chance to Maul, use an attack cycle addon to track your auto attacks and no matter what get that Maul queued up for the next auto attack swing. You can try swapping out more PvP gear for the clefthoof stuff as you get it. Just keep defense + resilience good enough to stay uncrittable.
AoE tanking as a bear...just swipe, swipe, swipe, and swipe. As you get bored throw in some mangles, maybe a lacerate or two. Should be just fine as long as your DPS is assisting you on your main target, not working on one of your side targets. Switching targets to mangle/maul/lacerate can be helpful to relieve the boredom or just double check that the threat is high all around.
Based on your gear, you'd think you'd have more health. I'd probably say that the low health is either a talent issue or that you've gemmed/enchanted your gear inappropriately?
13.3k isn't great, but isn't that bad unbuffed (and it doesn't sound like you are raid buffed). 10 man raid/food buffed you'd probably get up to around 16k, which is passable for a lot of Kara. I'd be more concerned with your total armour (it sounds like it would be low) as with low damage mitigation that 13.3k (or 16k) will get eaten up quickly! You'll make your healers work for their dkp! :-)
I agree with Sparks though re:hit/expertise... its a nice to have, not a need to have. Definitely don't gem for it. The gems/enchants on my gear are predominantly stamina and agility (and as the health goes up, the focus moves more on to agility for the dodge). What you should focus on gear-wise is gear with good armour, stamina, and agility (and making sure you are crit immune of course). Druids generally don't have problems generating threat, even with a few misses. As with Sparks i usually start with FF then mangle/lacerate spam, and from that point i rarely have aggro issues. If it is a problem at the moment, just have your team obey the 5 second rule (hands off the weapons until you've had time to gain a good aggro lead).
Also the gladiators maul is a pretty terrible tanking weapon. Sure it has good stamina, however Earthwarden overall is a much better and is a pretty easy to get rep reward. It also has expertise, which helps with reducing misses. The rest of the gladiator S1 stuff is averageish for tanking.. shoulders for tanking druids are hard to come by, so those may be the best option you'll find pre-Gruuls lair.. although you should replace the gloves as soon as possible with the T4 drop off curator.
Gemming for hit rating is a mistake. Just ignore the set bonuses; it's not worth going for.
There are a few priorities you should focus on. #1 is crit immunity, which is attained by 415 Defense with Survival of the Fittest, or 103 resilience, or a combination of both. You're probably VERY much beyond this point due to wearing both S1 gear and full Heavy Clefthoof. #2 is health, and gemming correctly is very much a requirement -- your yellow slots could provide at least 60 more stamina as far as I can recall (it's been a while). That's before bear form modifiers. #3 is armor -- as much as you can get. Don't wear rings without armor (yet), and don't use weapons without armor (ever). #4 is agility, again as much as you can get. This is better than pure Dodge rating point for point.
As for threat, the best thing you can do is get a proper rotation. I had no real issues with parries or misses on my druid. Mangle every time it's up, Lacerate on every other cooldown, and only Maul when you have excess rage. (The last shouldn't be a problem on boss fights.)
As for AoE fights, spam the hell out of Swipe. It works. You have to learn to position correctly as you will only hit the mob you're facing and the two mobs closest to him (this has nothing to do with whom you're targetting -- only the direction you're facing). By shifting the direction you're facing, you can hit them all.
Finally, don't neglect your DPS gear. As a Feral druid, your greatest addition to a raid is the ability to shift from tank to DPS with just a gear change.
ಠ ,ಠ Dovie'andi se tovya sagain - it's time to roll the dice