The reason why your poison is so high is because you used the jarrin root. It is extremely deadly and I've seen potions with it that can go much higher. The wiki says that jarrin root and deathbell can make a poison of 2400 damage.
You should have saved it as there's no way to obtain a second jarrin root except through the console.
Through normally obtainable ingredients, the highest damage poison I was able to make (while wearing 5 pieces of fortify alchemy gear, including usage of the falmer helmet glitch, all necessary alchemy perks and alchemy skill at 100) was this:
This was done with these ingredients:
For some reason, crimson nirnroot makes the strongest damage health effect @221, all other combinations do not come close.
Assuming the target has no poison resistance, this will end up being roughly 384 instant damage. Here are combinations of damage health with other effects:
Crimson Nirnroot + Giant Lichen + Jazbay Grapes:
The ravage health comes handy since it lowers the max hp of a target so they cannot heal themselves to regain that hp.
Crimson Nirnroot + Imp Stool + Slaughterfish Eggs:
If you do not care about instant damage, this is probably the highest damage poison you can make in the game with over 500 poison damage.
And finally, for a fun experiment, here is what my maxed out alchemist can make with a jarrin root:
Roughly 12.8k damage(take that Alduin!)
Best Answer
Specifically for gold there is an unknown formula for maximum gold value that can be pick-pocketed based on the level of the character's Pickpocket skill and which perks they have. This can result in situations where even a small change in gold value can result in huge swings in percentage chance of success.
2000 gold is a lot of gold, it's going to be pretty hard to steal it back unless...
One way to completely 100% guarantee a successful pickpocket attempt is to paralyze the target first. As soon as the victim begins to get back up, try to pickpocket them and you will be able to take anything no matter the percentage chance displayed.
It is good to note that if you pickpocket this way your level will not increase.
Source: http://elderscrolls.wikia.com/wiki/Pickpocket
Though on another website they seem to have the formulas for chance to steal on stealing items and gold
Base_chance_formula = ( ActorSkillBase + Player_skill ) × ActorSkillMult + ( TargetSkillBase + NPC_skill ) × TargetSkillMult - Detected
Stealing Gold or Single Item: ( Base_chance - Gold_amount / 10 - 4 × Item_weight + Sneak_bonus ) × Effects_mult + Light_Fingers + Night_Thief + (Cutpurse if Gold)
Source: http://en.uesp.net/wiki/Skyrim:Pickpocket