You'd have to split into multiple UTXOs in a previous block. An unconfirmed UTXO can only have 25 ancestors.
It was possible to have many more ancestors in previous implementations of Bitcoin. I wonder if any BCH devs / miners intend to push for a greater number again. I'd welcome it
I think you're right. Just a matter of getting enough momentum of miners to change the setting, but it may be good to just remove the setting entirely. It seems "anti-usage".
It's not trivial, but it's still fairly easy. w/bookchain we split coins into however many utxo is needed. memo could change to switch between 3-4 diff "utxo chains" until nodes supprt
Edit: Oh wait, you already more or less do that, didn't read the full thread before replying. Should be split automatically though if users are complaining about it.