There will alway be doubt at any decision one makes. Only time will remove the doubt bit by bit. And that goes both ways. Yes/no for CI.
People that choose not to let their child hear, and raise the child with signlanguage will also have their doubts about their decision. Only in time, seeing that their decision was good, that communication is established, friends are made, school is going well.. all these factors help to grind away the doubt.
Parents that make the choice for CI will have gone through an emotional process leading to their decision, and with it there will will be doubts. Will it work. How successful will it be... Only when CI is activated this doubt will be (for most) reduced when communication is established etc. like with the decision to raise a child deaf.
For me, and many other parents that have made the same decision, any doubts about making the decision TO have faded away. For some faster than for others..
The problems start - in any of the choices made - with communication. When this is not established from day 1, there will be problems. When the child cannot hear, and the parents don't use signs: there will be problems. When the child learns sign, but the parents don't: there will be problems. When the parents decide for CI, but do not establish a form of communication before the child can here: there will be problems. When a child has CI and the parents think that the problems are fixed now.. there will be problems..
When a someone that has been deaf all his/her life and decided to "try" a CI expecting to hear: there will be problems..
Any decision a parent (or any other person) takes regarding CI requires full involvement in the process. Whether learning to use sign language (fluently) or to (help) learn make sense out of the new input. No involvement - no success. And even with that.. success is not guaranteed..
Your child might be fluent in sign language, have many deaf friends, be happy in the Deaf world, but in a family setting the parents have to be interpreters.. Contact with the nearby family and friends is a problem. Your child might be able to hear with CI, but not enough to speak and listen to a conversation..
In the end, success is defined by expectations...
If you expect CI the give you hearing.. you might be disappointed. If you expect sign language is solving the communication gap, you might be disappointed.
But... when it works... when the decision turns out to be successful.. when all the studying you have done has paid off, when all the attention to your child proves to be working... parents have all the right to be proud of it, and to share it. Whether their child is deaf or can hear.
btw.. when you said "Even those who takes input from the deaf community or linquistics, are still under pressure from oralist."... this is perhaps even more strong the other way around.
The pressure from Deaf community might even be bigger. When part of Deaf community, one has to be very strong to consider CI.. Even stronger to go through with it.. Because... any hint of wanting to hear sounds is regarded as treason.. Let alone enjoying sounds....
Nobody wants to lose their family and friends...