The key element to a proper tanka is for the middle line to serve as a pivot that both connects and transitions from the upper poem to the lower poem. between. I don't always focus on that but when I do, it's a better piece.

Deaths’ facts differ still

Will drives lives’ paths to deaths’ dates

Love burns — searing pain

Deepest loss most room for gain

Endless pain, Light fills the drain

I know, tankas shouldn't use end rhymes. As someone said to me recently about poems, actually I think it was you, learn the rules then break them.

I also enjoy creating unbroken line tanka. 31 syllables, no punctuation. https://medium.com/illumination-curated/31-syllables-of-meaningful-engagement-for-writers-and-readers-e53c895b7021

I haven't done a nonet but I did do a couple of etheree reverse etheree, https://medium.com/channspirations/poem-of-united-purpose-and-place-in-and-of-the-human-race-d85f4103f047, and I enjoy using ascending syllable count stanzas within a free verse. This one has such an 11-line stanza. https://medium.com/channspirations/of-love-angels-and-god-a9b07615657b

I enjoy mixing forms. That one starts with an American cinquain (2/4/6/8/2 syllable count) and ends with a tanka