Is it technically demanding enough?

For what?

Sorry - it did say in the question's heading, but I think it was too long to show up here.

For a competition under the age of 25 (I know age means nothing really in terms of ability etc.)

Yes I'd have thought it OK, its about four and a half minutes.

I'd say it would demanding enough, but is it possibly too long? What are the stipulations for the competition?

The programme shouldn't be longer than 12 minutes...I though that, if played well, it would show good technique and cantabile playing. I don't know whether you agree...?

Could anyone recommend something quite challenging that would be a complete contrast to the Berceuse for a nice competition programme?

Third movement of Bach's Italian Concerto? (After the Berceuse, to waken 'em up again! If you've done a good job of the Berceuse, they should be gently nodding off... )

One of the quicker ones of Shostakovich Op34 Preludes eg No15 which is quite well known, or no 5 in D.
Or even no. 5 of his Op87 Preludes and Fugues.
Or'Aufschwung' from Schumanns 'Fantasiestucke'