The Darth Maul fight was a similar length to the Anakin/Obi-Wan fight, but the choreography was more beautiful to watch, and there were mostly practical effects at play there. It helps that there's no dialogue throughout the entire encounter, save for Ewan McGregor's "Big No" that actually sounds a lot better than any of the other "Big No"s in the series.
The finale to episode 3 involves Yoda fighting Darth Sidious, which is almost completely CGI, and Anakin and Obi-Wan constantly moving from one CGI location to the next; their fight choreography isn't as fun to watch, as it's mostly just the two of them wailing on each other like animals. At some points, the sabers are moving almost too fast for the eye to see, which makes one wonder just how much of the fight was practical and how much of it was souped up in digital effects to look better.
It kind of reminds me of a certain other lousy prequel trilogy...

Peter Jackson, your Hobbit action scenes are slapsticky, unrealistic, overly lengthy, and just all around disappointing. I couldn't believe that the same director who brought us that Aragorn vs. Lurtz fight at the end of Fellowship of the Ring went on to film complete duds like...well, just about every action scene in The Hobbit trilogy. You used too much CGI, Mr. Jackson, and you don't know when to cut down your scenes. You got melodramatic and phoned-in performances from your new actors. You used horrible comic relief. You wrote and directed each movie poorly. In other words, Peter Jackson has made all of the same mistakes that George Lucas did.
EDIT: 666th post. It's time for me to pay my dues to my lord and savior Lucifer.

There you go, you creepy b@st@rd.