IMO, the project should be the developer's, start to finish. Design by committee, or by poll, only waters down the developer's vision. Having said that, I can also think of two exceptions.
Firstly, seeking player input as a marketing strategy to encourage people to subscribe or pay more for the product. I see a lot of developer's using this strategy on Patreon, ie. in return for paying more, players get a say in how the game progresses. I'm skeptical that this strategy produces a better game in the end, but I understand that it may be an effective tool for making money.
Secondly, in some instances, having a different point of view, or input from others, can be helpful for a developer. It's easy to lose perspective when doing a game on your own. However, input through polls made available to subscribers is, IMO, likely not the best way to go about obtaining this kind of input.
I agree on most of your points...
As to seeking player input... I've seen it as well, where developers are using Patreon, and other sites like it, as a way to do business rather then to necessarily supplement themselves while working on their artistic creativity... Patreon was never really intended for that model, but it gets used that way by some folks, regardless... And a majority of the time, when those developers are basically placing some, or most, of the creative direction a VN/Game gets developed, in the hands of the paying fans, 9 times out of 10 it tends to suffer, because of it... Where it might have been welcomed more by the masses, instead it now is intended to only please those few fans willing to pay for the right to control the development... There is a difference between selling developmental control, and rewarding paying fans... This particular model is not a reward, but is a case of money over quality development... It's one thing to allow paying fans to give critiques and submit suggestions, but it's another thing to sell the actual control over how something is developed...
As to the instances where a difference of opinion, or varying fan input, is used by a developer... I've seen several cases where a developer believes their product is doing well, and it might actually be doing well according to the general public... But then some paying fans give a difference of opinion and either cry for changes, or apply pressure to the developer, into altering their product, to fit just those paying fans idea/s of what the project should be and/or the direction it should go... It may even be a case where paying fans stop paying, and the developer panics due to the decrease in funding, and shifts gears in order to pander to those, who dropped their sub's, usually in a desperate attempt to get them to resub, or get replacement subs... That kind of developer behavior happens more then folks think it does... Losing paying fans, may not even be directly related to unfulfilled requests, by the paying fans, but the perception that it did, by the developer/s, can still have a negative affect on development...
The use of Polls/Voting, works best when there are already predetermined/premade things created by the developer... Who then presents them to the paying fans for polling/voting... Things that are usually cosmetic rather then directly related to the story/plot/content... For example, stuff like Hair Colors, Premade Character Models, Eye Colors, Premade Clothing Options, Character Names, etc... Examples of things to shy away from in polls/voting, include basic lists of a bunch of fetishes, or plot points, or anything that might effect the predetermined story, increasing or decreasing the amount of planned erotic/porn scenes, etc... Because then you are basically allowing the paying public to directly control/drive the direction of the over all content... This usually in turn causes story/plot pacing issues, continuity issues, and sometimes game play confusion... It's not always the case, but I've seen it happen enough times to know there are real effects like those... The developer may not even notice, or get feedback about those issues, from the paying fans... Because the paying fan/s got what they wanted, and to hell with everyone else, in their minds... They may not even care that the overall development is suffering, because they got what they wanted...
I've seen a project get half way through production, with over a years development time invested, it was doing alright, but because control was slowly/quickly handed over to paying fans (for whatever reasons), suddenly either the project begins going a different direction, and/or completely changes from what it once was, and/or became a bit chaotic/confusing all of a sudden... I've even seen them start over from scratch, or begin a "sequel", when the original project isn't even done yet... Or the developer begins to get a bit bored, and/or has so many ideas, they begin a 2nd or 3rd project, and now has to split the load... In that particular case, I almost immediately have the word "milker" pop into my head... Because, by prolonging development on multiple projects, or by starting over after getting pretty far into the original project, it causes the time of development to magnify in length... Taking 2 times on upwards to 5 times the amount of time now, to get through all those projects... All the while, they are receiving subs from paying fans that initially climbed aboard before the split/restart, or are so blinded by the hope that they are going to, one day, get a finished product, and/or get that tiny bread crumb of content that took 1 to 3 months to get done, so now, the developer may get more money (from fans of all the different projects) for longer... It's not always the case of milking, but it is always suspicious when it happens, and is usually not viewed positively by the general public... Whom may have been following a given project for a while, want it to succeed and finish, but now it's gonna take even longer, or may never get finished in a timely manner (may even get abandoned in the long run, if one of the other projects is making more money for the developer then the other/s)… But because they can't afford or desire to donate, they are screwed... It may even feel like one or more of those projects are now being held hostage, until more folks start donating, at that point... It is a ploy used more often then folks think... And only if the developer is a studio of many different folks (far more then like 2 to 3 full time developers) working in unison, is there any real chance it will work out in the long run when splitting between multiple projects at once... And in cases where it was not intended as milking, it may still feel like it to the general public, in those few cases I mentioned...
Zip