The choice between sealed products and single cards depends primarily on your investment goal, how much risk you want to take, and how well you understand the Pokmon market
Considering fast mana cards like Mox Opal are banned in Modern, Ugins Labyrinth appears to be bonkers
I made a new list with him included and updated my post, so the updated list is linked
Blue Nami 1xOP03-040 4xOP03-044 3xOP04-041 4xOP09-050 3xOP03-050 3xOP07-054 1xOP03-041 4xOP01-088 4xOP02-066 4xOP03-054 4xOP03-055 4xOP06-059 4xOP07-055 4xST03-017 4xOP03-056 Blue Nami is a great budget tournament deck to beat the likes of Black Rob Lucci , Yellow Enel , Black Teach, Black Yellow Luffy , and Green Bonney
Or if you want to give EDH a whirl, the best Commander precon decks are a handy starting point.
I especially enjoy the series themed around famous artworks and often buy them