It really depends on your commitment to learning. As a side hobby 10 minute commitment while commuting – yea its a great idea. But with the goal to actually learn the languague it is not. Premade decks are like duolingo or like learning vocabs in the school, sometimes a bit useless and not really what interests you.

For me the deck that I use right now is kinda nice and I enjoy it. It focuses on vibes more than completness in hello-goodbye styled topics. Like a few cards about teineigo and conjugations of it to get a feel about it and then it moves on. But yea I am not much into languague learning and I would say it is a huge part to creating the deck after your needs. I just learn for a few minutes a day and have long breaks, its not my priority to actually learn japanese I only want some knowledge to understand anime better and it does work.

It can be a good starting point. Learn a fun deck and when you’ve done that and you are at a stage where you can comprehend enough, then you can make the effort for the extra vocabs that you encounter yourself. Altough I have found a lot of stock-audio-file decks that are boring af, so I am not sure if I’d recommend if I didn’t have that japanese anime deck.