Not being a Cake user myself, I wasn’t aware they were working on a Breez SDK feature. Seth’s not as active on Nostr as the other place, but as the ops lead at Cake I imagine he’d have a lot of insights into this topic. I’ve seen him post some positive things about Spark, including in this article he published a few days ago.

https://bitcoinmagazine.com/technical/spark-and-ark-a-look-at-our-newest-bitcoin-layer-twos