The Kodrcha-Tzameshut Archaeological Complex (KTAC) is an unattested substrate for Tsrovesh.
Some sunken islands?
Could some Clofabosin words come from the complex (like isradipine)? (it's an excuse to borrow some generic drug names in Tsrovesh)
Qbit minus the ejective part? Or just /q/? (resulting in tsrovesh doublets with a glottal stop alternating with k)
Tsrovesh with more sounds? (including θ, ð, q, and some Ubykh sibilants)
Words relating to: flora and fauna, naval technology?
It should contribute to over 50% of Tsrovesh basic vocabulary