Increasing output 10 times will also (more or less) drop the price 10 times, which might scare both possible future investors and current holders that might just panic sell, pushing the price down even more ...

Now the price is around 300 satoshi, but once (if) it gets to about 2-4 satoshi range or less, it becames a bit difficult to trade due to most markets not having prices with fractional satoshi cost. That might ultimately kill the coin.

With bitcoin, everybody was scared that Satoshi has 1000000 BTC and what effect on market that would have .... and in the end, it had no effect, except for "scared" people.

I guess most of these unaccounted CACH are already dead or forgotten and while some parts might resurrect if somebody founds a lost wallet, it will happen randomly and over time.

I think good idea would be just to keep current output, but in a similar way as bitcoin halves its rewards over a long time frame, use a similar scheme.
The mined amounts would (perhaps more gradually instead of halving at regular intervals) decrease. That might create a currency with slightly "deflationary" trend and make it more attractive for miners, holders, investors and merchants to accepts (as the price would not drop, but with well-estimated gradual decrease, the actual value of one CACH might be more or less stable in time)