"I already have a well established and successful sheet training plan using tabs, standard notation, technique instruction and grades. How I would incorporate Yousician best?"
It's great that you have built up all these resources already. Yousician can be a great addition to your existing tools & practices.
Your students wouldn't have to go through the Yousician syllabus - of course they’re welcome to use any or all of it if desired, but if you’re using another syllabus then that’s great too. Instead, the core idea with Yousician is that it’s a massive library of high-quality, engaging, interactive, searchable content, which can be used in a wide variety of ways.
For example, in the "Songs" tab you’ll find playlists of songs in a wide range of genres and techniques, all organised by difficulty level. This makes it easy to supplement your existing syllabus, and provide plenty of great content for say an intermediate metal player, or a beginner who needs extra work on their cowboy chords, etc.
We also have weekly challenges, which many teachers use to encourage their students to work hard and climb the leaderboards. Or you could search the thousands of user-created songs, and add your own to give your students tailored exercises that fit their needs.
Since all of this content is engagingly presented and gamified, teachers are telling us that their students practice much more regularly and with greater attention to detail than they would with a normal printed page.
The best way to explain is perhaps by sharing how we hear other teachers use Yousician and how they incorporate it in their lessons. Matt Poole wrote a short but great article on what he thinks gives most value for his students.
Also, while we did not expect this, we have heard many times is that Yousician works like magic with students that might have difficulties concentrating or sitting still otherwise. In group lessons, the social aspect of playing together and going for points and stars at the same time seem to be very motivating.
The Practice Mode with the ability to slow down and loop on certain parts of a song are very useful. This can then be combined also with your own material that you can also add to Yousician if you like.
Perhaps the best would be to discuss with other teachers how they use Yousician with their students in conjunction with their existing material. The YousicianEdu group on Facebook is a great place to do so.
Every teacher uses Yousician in a slightly different way. I am sure you’ll find ways to use it that we haven’t even thought about. It happens quite a lot that teachers invent innovative ways in which to use Yousician as part of their lessons.
So, we’d probably encourage you to just try it as part of your lesson and see how your students react. We'd be delighted to hear what you think.