I'd like to see what you come up with. Sounds like a good idea could get full capacity with any risk.
I also in progress to build a LTO for another purposes (car starter battery)
My plan is to use protection board of Super capacitor to regulate the charging voltage....
Afaik the protection board will be limiting the maximum voltage but there is no current regulating....
And since it using TL431, there is possibility to "adjust" the target voltage output by change the value of resistor R1 and R2..