As an online Poker player, the most important factor for me is to make sure that all my co-players within the table is a legit person and not a bot. It is my most concern of all things in poker and until I don't know how to verify it unless they are chatting in the chatbox. 
Well you can be playing with a bit while your opponent chats with you. It's just difficult to verify from he other side unless you use video chat perhaps that's the only way and I think that's difficult to achieve at this time of online poker gambling development.
Collusion is detectable.
I can imagine that it's pretty easy to circomvent detection on all the smaller sites that are running with a much smaller team.
I guess the smaller sites possibly also have some minor collusion detection options to their disposal, but nothing that can't be beaten by people who are smart enough to trick the system.
Players running bots on their accounts is also something that's going to affect online poker on a much bigger scale in the future, again mostly on smaller sites though.
I would never play with big money on smaller sites.
even if the site is big, i would never playing gambling with big money because i know the risk and i don't want to makes me to get loss too much money. maybe i can only use small money to playing gambling and spend that money with 3 times of games and after that, i can leave the places without spend all of my money.