Beyond the Overlook trail snapshot
Effort8/10
Our day~11 miles
Best partGlacier views
Our pickS3
SkipS4 extension
Worth it?Yes
The glacier views justified a full day
What made Skaftafell special was seeing the glacier from above and being able to trace how much farther the ice once extended. The scale is difficult to appreciate until you are looking across the entire valley.
Why we would not add S4 again
The S4 / Kristínartindar extension felt unnecessarily dicey to us. The route was not clearly marked in places, there was a lot of very loose rock, and the additional views were only marginally better than what we had already seen. We would choose S3 and enjoy the day rather than adding risk for a limited visual payoff.
Our recommendation: Make Skaftafell a real hiking day, but do not assume the longest extension is automatically the best version.