PT Character parallels (Force Awakens spoilers if you haven't seen it).

Just like the original trilogy, the prequels have three lead characters; two boys and a girl.

Since Luke and Anakin are both aspiring Jedi, and Leia and Padme both politicians, it was easy to see them as equivalent characters. Obi-Wan was quickly assumed to be the new Han Solo type, particularly with Lucas saying that Ewan McGregor was the "perfect young Harrison Ford."

Looking at the prequels now, I can't help but think that the roles are actually flipped: Obi-Wan is more like Luke, while Anakin is more like Han. My case follows:

Luke/Obi-Wan
1. Luke was originally written as an older Jedi Master, complete with grey hair and a beard, just as Alec Guinness's Obi-Wan first appears to us.

2. The young Obi-Wan was originally written as a fully fledged Jedi Master, dressed in black, just as Luke was in Return of the Jedi.

3. Both watch helplessly, screaming in protest, as their mentor is cut down by a Sith Lord.

4. In the middle films, each of them is the one who goes off on the solo mission while they other two characters become romantically involved.

5. Both are the first in their respective trilogies to speak the line "I have a bad feeling about this."

6. Luke is sent to learn from Yoda, just as Obi-Wan had done.

7. Luke constructs his lightsaber to resemble Obi-Wan's.

8. Luke loses an apprentice to the Dark Side.

Han/Anakin
1. Luke and Obi-Wan need a pilot to get them off of Tattooine. Qui-Gon and Obi-Wan need Anakin's piloting skills in the Pod Race to get them off of Tattooine.

2. First (and only) character in their respective trilogies to say "Here's where the fun begins!"

3. Han has fallen in with a crew of criminals led by Jabba the Hutt. Anakin has fallen under the influence of Palpatine. It falls to Luke to rescue each of them. One could argue that the rescue of Han at the beginning of Jedi is merely practice for the larger rescue at the end.

4. Anakin becomes romantically involved with Padme while on a mission to protect her. Han becomes romantically involved with Leia while on a mission protecting her.

5. Anakin's floating stretcher on the way to surgery is not unlike Han's floating slab of carbonite.

6. It is Han's son who follows in Vader's footsteps.

7. Vader is offered up as bait, to be killed by Luke and complete his journey to the Dark Side. Han, as we all know, is not as fortunate as Vader was.

The opposing arguments:
1. Luke, like his father, undergoes Jedi training. They both lose their original mentor to be passed on to another. Both lose their right hands in a lightsaber duel with a Sith Lord. Both later return the favor in the presence of Palpatine, and are goaded by him to commit a revenge killing.

2. Han and Obi-Wan are both heroes in their respective trilogies, only to be killed at the beginning of the next one. They also both provide exposition about the villain of the film.