Love the extended mountain story so far, gestaltist!
I was bored, so, on a whim, I took the nine definition-less example words from my latest post in the Project Ypsilon thread, and applied the appropriate sound changes (which I now realize need one or two adjustments) to them to get the words' expected descendants in Proto-Western-Ypsilon.
/ˈgːoɐ̯ɻeɪ̯n/ > /gːoɐ̯ˈɻeːn/ ggoareen
/ˈjat͡ʃːxoɔ̯muʔ/ > /jat͡ʃːʜ̩aːˈmu/ yačšḥaamu
/ˈiθŋaɔ̯ːpːl̩haːɻ/ > /isŋoːpːɪˈʜaːɻ/ isŋooppɪhaar
/hd͡ʒimˈβːokʟaɻ/ > /ʢ̩dʑɨmβːoˈklˠaɻ/ ɦ̣dźɨmββokłar
/sːeɔ̯ːˈgːɻ̩ɸn̩məs/ > /sːeɔ̯gːəˈɸɪ̃məs/ sseoggəɸɪ̃məs
/wiɔ̯tːm̩ˈðəːʔroɪ̯ːn/ > /woɨtːũvaːʡ̩ˈroɪ̯ːn/ woɨttũvaaq̇řoîn
/ʒːoɜ̯lˈin/ > /ʒːʉˈəlin/ žžʉəlin
/ðk͡xmadːuɐ̯ʃˈuʔ/ > /s̪kxmədːuˈaʃu/ ṩkxmədduašu
/b͡βoɻimunˈaɻ/ > /bβəˈɻimunaɻ/ bβərimunar
It's meant to be the most phonologically conservative daughter language, and these are only phonetic changes, but in all honesty, a very small and not very practical part of me is still disappointed that the daughter forms came out so similar to the proto forms. So, based on some currently pretty poorly-defined ideas for what sound changes will take place over the next 4,000-5,000 or so years after Proto-Western-Ypsilon:
/gːoɐ̯ˈɻeːn/ > /ˈʑøɽe/ jöṛe
/jat͡ʃːʜ̩aːˈmu/ > /ˈjaʃamo/ iaşamo
/isŋoːpːɪˈʜaːɻ/ > /ezˈnøfexæ/ eznöfeḥä
/ʢ̩dʑɨmβːoˈklˠaɻ/ > /aʑdemˈvogla/ ajdemvogla
/sːeɔ̯gːəˈɸɪ̃məs/ > /xeɔ̯ˈʑem/ ḥeojem
/woɨtːũvaːʡ̩ˈroɪ̯ːn/ > /voθoˈvaæ̯roɪ̯/ vothovaäroe
/ʒːʉˈəlin/ > /ˈʃare/ şare
/s̪kxmədːuˈaʃu/ > /skamoˈvaʃo/ skamovaşo
/bβəˈɻimunaɻ/ > /boˈɽimna/ boṛimna
These forms will almost certainly change as I actually set down lists of sound changes, and as I figure out other kinds of diachronic changes. This was still fun, though. Based on the amount of time separating Proto-Western-Ypsilon and these hypothetical forms, these would be words in Zendlektek/Netonese, my "first conlang" that I'm trying to eventually remake diachronically.
The orthography I've used for Zendlektek/Netonese above is pretty phonemic, but I'm not sure if that will end up being the orthography I actually use, or if I'll go for something deeper. For example, the Proto-Ypsilon dative plural form of ssēoggṛ́fṇməs
/sːeɔ̯ːˈgːɻ̩ɸn̩məs/ is ssēoggṛ́fṇmūvə̄
/sːeɔ̯ːˈgːɻ̩ɸn̩muːβəː/. According to regular sound changes alone, those become sseoggəɸɪ̃məs
/sːeɔ̯gːəˈɸɪ̃məs/ and sseoggəɸɪ̃muuβəə
/sːeɔ̯gːəˈɸɪ̃muːβəː/, which, far in the future, may become (phonemically) /xeɔ̯ˈʑem/ and /xeɔ̯ʑeˈmygø/.
In the phonemic orthography, these two forms would be written as ḥeojem
/xeɔ̯ʑeˈmygø/, but, in a potential deep orthography I came up with, they could instead be written as shéoghehémes
/xeɔ̯ˈʑem/ and shéoghehémúweh
/xeɔ̯ʑeˈmygø/. Those spellings kind of look Goidelic to someone like me who's largely unfamiliar with Irish, Scottish Gaelic, and Manx.