All cat FS cabins are big and nice with great balconies. Those on deck 9 -like ## 9394 and 9694- may be a little "sunnier" than those on the deck below.
When in port there could be ships berthed behind you, but why stay on the balcony then? I donīt think you should try to compare an FS with the RS. The latter is intended for two guests, whereas the FS can accomodate up to eight (even if I would say four or max six is better).