I really enjoyed Episode I!
I wasn't born when the first trilogy was released and I still haven't watched all of the older old movies.
But I really like the realistic motivations and politics behind the plot of Episode I. They make the film be almost like "a kid's introduction to geopolitics".
The main reason I liked Episode I is how freaking cool the Gungans and Naboo architecture and weapons look like!
I personally feel like they are of the most visually striking art pieces I've ever seen in a Sci-fi movie (specially Naboo, which makes them feel a otherworldly civilization even tough they are also humans).
On the contrast, Episodes 7-9 bring almost nothing new in terms of cool sounds and visuals. Have you noticed in the three films there is a new desert planet without a major civilization on them?