I dont think it has to be too complicated, Main point is that each group get 5 teams from this top 20 Instead of maybe 10 or 15 of these teams together... If you want to categorize anyway, it´s easy just to draw top 4 in separate groups and 5 to 8 in separate groups, 9 to 12 and so on... Just choose EASHL ranking as our seeding rank, I myself would prefer 6vs6 since that´s what we are playing for... then everyone know in the future that if you want to be seeded move up the eashl ranking. If theres is 1 or 2 really good teams that havent played enough to be seeded, It doesnt matter as they wont mess up the groups anyway, and still get their spot. You can draw a parallell to soccer championships where you have to move up the UEFA coefficent to be seeded, and seeds have a big factor to the standard of a tournament, but still it doesnt mean that lower seeded teams are worse or cant win, it´s just balanced groups.