For more info on the spikeyness and rng. This is what swinging with a weapon looks like in EQ:
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On that number line from 8 to 35, is the min to max of the weapon being swung. You see that sweet spot most hit for dmg of 25? That moves up and down the graph depending on how high AC is in relation to the opposing parties ATK. If your AC is higher than the mobs ATK, they'll swing on the low end of the chart more often, if you're AC is LOWER than the mobs ATK then they're going to hit more often on the higher end of the spectrum, thus more big hits, spikier damage.
Warriors melee hate generation is dependent only on potential damage, not how much the hit actually lands for, so their ATK is irrelevant in terms of hate generation, but the mobs ATK in relation to their AC is what effects how much they're getting hit for.
The spikey RNG you're seeing is when the tanks AC is likely below the ATK of the mob he's tanking.
Tl;DR
Focus on the ac softcaps and make sure you're above them for the content you are tanking
Create a weapon build to gain hate exponentially comparable to all melee dps in the group so you are constantly outpacing your dps at every turn for hate.
Have a backup plan in case of emergencies, buy root nets and keep them recharged and ready at all times. Treat taunt like a root net with a failure rate.