I don't like this question because Mid Lane is already one of the hardest roles no matter what point of view you look at it from. Starting mid-lane requires already having knowledge in other lanes, because the stress you undergo being in the very center of the map is much higher than that of being on the far corners. However, some more simple mid-laners to LEARN (It won't necessarily make you good at mid-laning, you just won't be pressing random buttons hoping you'll burst the enemy down) are Ryze Annie Lux Brand Ahri and Veigar. Each of these champions are relatively simple to LEARN, but not to MASTER. Ryze is not very strong number-wise and his combo is tough to get right. Annie requires mechanics to make the most out of her stun passive. Lux takes a lot of laning knowledge. Brand is strong in my opinion, but his combo is (once again) hard to get right. Ahri is simple, and like said above, you can correct yourself with her ult. She's a strong choice in any elo. However, her abilities aren't as straightforward as maybe I would like. Veigar is my favorite: however, without consistent farming, poking, and zoning you won't be able to make much out of him. You can check out my Veigar guide for beginners if you'd like. I hope this helped- good luck.
Her 3 dashes allow you to escape a lot of situations, or correct yourself after making a mistake.