From the perspective of a Magical Traditions Nerd
So there aren’t hard and fast rules for these types of system (outside of Dramaturgy - which might be an interesting idea to look at for inspiration.)
Another source to look at would be the rituals themselves, many rituals give multiple runes and this might give you some inspiration about how to use them. For instance Bravash + Irremais you have the abundance that comes from cutting away the weak. (It might not be the only way to combine the two you could play with the Goat aspect of Bravesh and be about the knowledge of driving off what has once caused you harm.)
“accepted pattern of some kind with greater and lesser elements”
As far as I am aware this doesn’t exist, but it’s a cool element to develop for your personal style. I do note often without other reasons rituals tend to start with the stronger rune magical symbol (unless they have another logic for progression of symbolism.)
On the overlaping them one difficulty might be how modular they are using your example of combining Orphis, Verys, and Tykonus could you distinguish that for switching Orphis to Diras, or Tykonus for Ull?