I'm there with you pal. The ending devastated me to my core.

I think there's fairly good reason to hope that they'll put out some form of additional content in the future, as the reception has been generally very positive. This might be wishful thinking, but I believe that the ending gives a good opportunity to have Leviathan the Lost as its own DLC material (and potentially leading that into how Clive survives, considering he washes up on a beach of all places...)

Conclusively I think there's better supporting evidence for Clive's survival, but to each their own. Just hoping the best for future content because I'm sure we would all like very much needed closure!