I have the same impression as you do and it is the approach I’m taking. I hibernated everything above my WK level and now I am unlocking those cards as I progress through Wanikani. For example, this week I leveled up to level 21. So what I did was unlock all the cards with the L20 tag and then lock again all the cards that have the WK tag. For the time being I am excluding the Vocab taught in WK to avoid burnout.
@Neicudi: Is it possible to use boolean like operators in the Advanced search? For example: Show me all cards with the Tag L20 that do not have the tag WK.
@hinekidori @jprspereira : Are @slither and myself correct in the assumption that all words with an LXX tag and not a WK tag are words not taught in Wanikani and that do not contain any kanji above Level XX?