Using Anki Subdecks Correctly

As I study a language, I have two sub decks under a main deck. Each of the sub decks have card templates overrides that populate the deck. I am planning on adding more card templates with overrides to additional sub decks as I achieve different levels of learning with the language vocabulary. Level one is Recall English meaning of Japanese word displayed in Kanji/Kana. Level 2 is recalling the Japanese word from the displayed English. I am planning on a Level 3 to do writing practice of the Japanese word in Kana from displayed English. Then finally, Level 4, one day far in the future, write Japanese word in Kanji from displayed English.

The reason I organized it this way was to master deck has all the notes with all the info for the vocabulary. The sub decks display different levels on information.

Are at least I thought was going to be a good approach. But now I see that when I complete all the new cards in Level 1, there are no new cards available for Level 2. I assume this will be the case for Level 3 and Level 4 as well when they are created.

The specific question; What is the impact between schedulers 3 on the pc and schedulers 2 on AnkiDroid? The website says they are compatible, but goes on the explain there will be differences. Also, do the stats of cards in one sub deck impact the stats in another sub deck? I am hoping no? I suspected that the cards would have their own pass/fail/recur statistics. My ability to recall the English meaning upon seeing a Japanese word in the wild will be quicker and more easily maintained than my ability recall the Kana/Kanji writing of a word off the top of my head.

I am also interested in thoughts on the this approach… I probably will not be easily swayed to using a different system. But I am open to researching a systematic approach to learning how to recgonize → recall → write words of other languages.

In terms of how much card should be “delayed” to the next review the V2 and V3 schedulers are identical in my knowledge.
The differences are in the order in which you will get cards to study. Also V3 has more customisation options for ordering.