Basically, I was playing using CACO, and got real tired of having 50 different potions in my inventory which provide slightly different effects. As a result I wanted to stack them. In short, the mod should be very convenient on any character that specializes in alchemy.

Notes: 
This is my first mod, so I'm fairly certain I've goofed a number of things. Lemme know.

Install: 
Install with your usual mod manager, should just work.

Compatability:
Should have 0 compatibility errors with other mods, but I really don't know. Tested with the most recent version of skyrim and skse64 (2.0.17). Given how I used address libraries, it might even work on different versions of skyrim.

This mod allows players to combine any potions in their inventory to generate new potions which have the average effect value of the provided potions/poisons. For example:
Potion of health - Magnitude 50 + potion of health - Magnitude 20 = 2 x potion of health - Magnitude 35.
However, the mod also allows users to combine potions with completely different effects, i.e.
Potion of health - Magnitude 50 + potion of magicka - Magnitude 50 = 2 x potion of health & magicka - Magnitude 25.

Whether the result is a potion or poison is determined by whichever there is more of in the contributing potions. Note, the scaling and averaging effect applies to the magnitude of the effect, so if you're using potions or poisons which scale based on duration, the mod will arguably be unbalanced.

Usage
Select a potion in your inventory and press T, this will bring up the combine potions menu. Add the potions which you would like to combine and exit, which will bring up a new menu with the result of the combination. You can either accept or deny the result. Should you deny the result, your original potions will be returned to you.

To distill potions, the process is identical, except you press left control with a potion selected instead of T.

-- Old Description, applies to 1.1 and earlier --
To use, add the combinePotions item to your inventory via console. Open your console,
type: help "Combine Potions" 
this will bring up a list of items with the id combine potions, which is the item we'd like to add
player.additem (id of combine potions) 1.

Then use the provided item. This will then open a new inventory to which you add the potions which you would like to combine. Exit that menu, and you will be brought to a new menu, here you can see the result of your potion combination. You can accept by taking the created potion, or decline by closing the menu. Closing the menu will return the original potions to your inventory.

Update 1.2
Mod is now scriptless, removed combine potions and distill potion items, instead the features are accessed via keypress.

Update 1.1
Adds the ability to distill potions, concentrating their effects. Distillation interface occurs through the "distill potions" item, which can be acquired in a similar method to the "combine potions" item. Interface and usage is almost identical, except instead of getting the average of the combined potions, the resulting magnitude of the effects is that of the incoming items added in quadrature. Example: restore 50 health + restore 50 health = restore 70 health.

Credits:
KMXUtils - Examples of some persistent potion creation
skse team 
The homies over at: https://github.com/Ryan-rsm-McKenzie/CommonLibSSE/wiki for teaching me how to write and set up plugins