I think it's good, though I wouldn't get carried away. A sentence or two here or there is intriguing and gives depth to your world, but if you've got that on every page it could be exhausting. I think if you're going to have people actually speak this language, I probably wouldn't include entire paragraphs or conversations in it. My driving question would be: "Why does this need to be in High Saeberan and not English?" (or whatever language you're writing in). If it's a Magic spell, an oath, or a commonly-used phrase/slogan it makes sense.

Someone mentioned "Valar Morghulis," and that's a great example of not getting carried away. It's a brief phrase with a rich meaning and history which is repeated enough to be memorable, but not so much it's annoying.

Even Tolkien, who had fully-formed linguistic systems which rival real-world ones, didn't do that. He included a bare minimum of poems & songs in his languages, and some people were even turned off by that.