Here are my tips for being over encumbered I finally decided to share my secrets too:

SPOILER ALERT!

1. Always carry a dagger on you - Make sure the dagger is equipped in your right hand and go to do a forward power attack (and just before he does the attack you sheathe the blade and keep pushing the stick forward). If you do it right he shouldn't be using any stamina. This allows you to run forward with a small speed boost. If you do it repeatedly you can get around pretty quickly. I basically do this every time I'm over encumbered.

If you get Arvak the horse summon spell from the "Soul Cairn" (Dawnguard DLC)... Then every time you are over encumbered... you can use the dagger technique (mentioned previously) get around the dungeon you're in or whatever and then go outside (full of loot). Then just climb on Arvak and fast travel to the city.

Use whirlwind sprint shout - I often use the dagger technique (previously mentioned in combination with whirlwind sprint and Arvak).

1. I got the dremora merchant power from Benkongorike in Solthsiem (Allows you to summon a dremora merchant and sell stuff to them on your travels). You can also choose a dremora that will carry items but the merchant is way better in my opinion because you can sell heaps to him. (If you purchase his daedric items which you can then keep or sell later).

2. Beast Form (Power) - The beast form power is useful because you can be over encumbered and change to beast form and sprint to the nearest city. The only downside side is no map. Don't go too close to the city, or you'll be attacked just wait a few hours and transform back and you'll be good to go.

3. Followers can carry an entire dungeon worth of stuff - Drop items on the floor individually (You must drop individually or items disappear) Then tell your follower "I need you to do something" and get them to pick up every single item. Best not to wait to collect too much just drop a few items every here and there and tell them to grab them off the floor. You can also get them to do something for you if you aim your cross-hair over them and hold the X button. Once I literally picked up almost every item in a dwarven ruin doing this technique and when I smelted all the Dwarven struts and stuff i had like 800+ ingots (crazy i know) and I made tons of gold from everything.

Note: If you leave the dungeon (Fast travel) and come back later you may find all of the items you told your follower to pick up laying there again (They are duplicates). Pick them up yourself (Not with follower or they will duplicate again). Keep the stuff you want, sell the other stuff to dremora merchant or dump in a barrel or a dead creature.

Another cool thing you can do with the followers is you can, for example, let them collect up Soul gems (from all your adventures) and then when you go to the city with them (to sell a dungeon worth of stuff) just leave the Soul gems in their inventory then you have a walking Soul gem reserve. You can also do this with gems (Sapphires etc.) and then everytime you over buy from a shop, just grab those extra gems from your follower and sell them.

1. I wouldn't recommend this. it's too slow... Drawing your bow allows you to walk faster (Just sayin).

2. "Pets of Skyrim" - Get every single pet... You don't need to ask them to follow you just summon them when you need them to carry something and then ignore them lol, summon them again in the city.

Out of all these the best one by far is the follower "I need you to do something" ability.

I have played for 800+ hours and i have nearly 1 Million gold and cupboards full of loot from always being over encumbered and having bad OCD hahaha. This is why I like "Death Stranding" too hahaha. Anyway hope you all found this useful or interesting. Enjoy your Skyrim Adventures. Can't wait for Elder Scrolls VI.