As for the main drawback of MDFCs (coming into play tapped), it is a concern, but not a huge one
It is going to feel pretty bad if the game reaches a point where you run out of counters, but tapping something down 4 times is often enough to get you there anyway This reminds me a lot of Jodahs Codex
This deck has everything you need for a competitive Commander deck, with brute force damage, plenty of card draw potential, some decent ramp and card cost reduction, as well as plenty of diversity amongst the creatures to always keep your opponents on their toes
Because Japanese pokemon cards are largely available only in Japan, they can be challenging to source abroad
If there are no cards that can be legally returned, then you cant pick one
Historically Sheldon handled many of these expenses out of pocket, resulting in a disruption with his passing