Phanphlle86
In my opinion, the Gornergrat is better as the Jungfraujoch. You could choose cheaper excursions in the Jungfrau region, for example Schilthorn or Männlichen. You can use the pass until Grindelwald, Wengen or Mürren (via Grütschalp).
Another hint: never buy tickets for mountain excursions in advance. If the weather is bad, it is very expensive to see only clouds and fog.