As i see many times the owner is very active and accept many suggestion when kingdice starting.
But i'm havent invest bankroll on it. so u need to check more.
Activeness is does not matter here, what investor really need is good traffic, of there is huge traffic on their site. I believe what they dream of will be paid. As long as there is many players here, more bankroll will come so there will big whale too and investor will get their money soon enough
For OP, I can recommend some sites which has great investment history like crypto-game, bitvest and yolodice. These are the best as I see for now
I did invest in these casinos and it is look good for me. I would, however, agree with BTCevo's point about whales investing. The problem here is that they can just eat up the whole investments and just take the whole big chunk of the pie. They will profit more but they will also be risking to lose more though.