Recently my guild (with me as MT) has progressed right through BT, and more and more am I hearing complaints about my threat (nothing new here =P ) but... even now i am thinking i should be putting out more threat.
For fights like Sunwell, Illi and even Council i am in full avoidance BT/Hyjal gear and my threat output probably peaks at around 1200 on Omen, usally it can sit as low as 900. This is with using the standard rotation all the time and HS when i have the rage. I have read the majority of the threat threads on this site (including Xav's excelent guide to generating The Threat)
On easier fights and trash i sub in alot of the expertise badge gear, sometimes (depending on the encounter) some of my DPS/crit gear. (Most of the time i have about 40 exp and 145 hit) Even still i am only averaging about 1000ish over the course of the fight.
I know i can do better as a new OT came in last night and was outputting 1400+ TPS on the trash, but i am at a complete loss as to how to achieve this outside of what i am already doing.
One thing that you can do, and should do is to make sure you always have a TPS, Avoidance, and a Stamina set for tanking. I've watched so many tanks that just use one set of gear for every fight, every raid and it doesnt change. In your case you need to get yourself a nice TPS set. Your TPS set should consist of Expertise, Hit, and SBV (Shield block value). Expertise is now the number one threat stat for warriors. I suggest getting the blue throwing weapon from normal MgT 3rd boss, then do it on heroic for the expertise trinket, along with using the auto-blocker for threat too. Everything else depends on what kind of gear you have DPS/Prot wise.
Heres my armory, im in my TPS gear which is at the tier five level atm.. i still need that throwing weapon and trinket >.>. Feel free to send me a PM if you have a question.
I'd first look to your ability to stay on rotation, and if you're using HS appropriately so you don't starve yourself on rotations. That is usually the culprit for many people, long before gear enters the picture. Use WWS to check your rotations if possible.
The hit cap for bosses is 142, you have 160. (The hit cap for trash is 95-ish, so you are way overboard there). You have room for 30 more expertise skill against bosses.
Why would you use your max expertise only on easy fights? Expertise reduces parries, netting a reduction in incoming damage on bosses who benefit from parry haste, while being twice as good as hit for threat generation until you drop dodges from the mob's table - at which point it is merely as good as hit for threat generation.
First easy step is to bag those Praetorian legs and replace them with 2.4 badge legs which will put you to 142 hit and raise your expertise. Get a Shard of Contempt. Find a bit more expertise where you can, up to 57, then backfill with SBV (e.g. Destroyer shoulders are better than Onslaught for a threat set). If you can cap hit with capped expertise, you're golden. If not, prioritise expertise over hit (where it makes sense to - wearing a blue expertise ring instead of the Supremus ring is dumb. Use your judgement.)
Now you have a nice threat set for RoS/Teron (though probably with too high avoidance even still). Next step is to make sets for bosses that aren't threat sensitive at all (Mother, etc.) or require high avoidance or high EH or whatever. A one size fits all gear set is suboptimal from the start.
A trash set needs 95 hit, 23 expertise, and the rest focused on SBV. Anything more than that in hit and expertise is wasted.
Thanks HEAPS Satrina, ive reworked my threat set and i did have the trinket and the 2.4 legs, i managed to get a trash set with capped expertise and hit with 800 BV and the Auto-Blocker and the trink off Saph, my Boss one has capped hit and 50 expertise with 500 BV (only one BV trink coz of the Shard)
the ideal group for my would be; 1)me the tank, 2)an MS warr (for blood frenzy) with imp shouts for battle shout, 3)an enhance shammy for wf totem, 4) feral druid for leader of the pack and 5) a hunter ours is usually survival
I am sure this sint your prboem but I was only managing about 1000 TPS aswell. One day I happened by the trainer to try and respec to Fury for giggles and discovered I had never trained SS and Dev above rank 1 .. lol.. needless to say doing so has me about 1500 TPS on a fight with good rage... i am only T4/T5.
I also made a "threat set" with more hit/expertise, got some new biyts of badge gear and regemm'd some of my old DPS bits for more threat.. all of that .. new skills, threat set, picked me up about 400-500 TPS.