IMHO, Yitroh's advice that was supported by Moses and God, of dividing the people into groups of 10,50, 100,1000 completely disregards the tribal structure:
וְאַתָּה תֶחֱזֶה מִכָּל־הָעָם אַנְשֵׁי־חַיִל יִרְאֵי אֱלֹהִים אַנְשֵׁי אֱמֶת שֹׂנְאֵי בָצַע וְשַׂמְתָּ עֲלֵהֶם שָׂרֵי אֲלָפִים שָׂרֵי מֵאוֹת שָׂרֵי חֲמִשִּׁים וְשָׂרֵי עֲשָׂרֹת׃
You shall also seek out from among all the people capable men who fear God, trustworthy men who spurn ill-gotten gain. Set these over them as chiefs of thousands, hundreds, fifties, and tens. Exodus.18.22
On the other hand, from Hilchot Sanhedrin we know that the judicial structure is bound to tribes (a lower Sanhedrin in each).
Why does Yitroh's advice disregard the tribal structure of the Hebrews?