Seems like common courtesy. They did make the suggestions site after all.
I mean... that's the kind of thing that would make me regret putting up a suggestions site in the first place as a developer. I stand by my stance that this level of community interaction is rather uncommon, rare even, though of course each person's own experiences may perhaps differ elsewhere.
Seems to me they made the suggestions site because did care about the community suggestions, so that suggestions wouldn't be lost in the forums. Not to mention the amount of suggestions actually implemented from the suggestion site. The unfortunate result of showing that they care, and having had some history of responses, seems to have resulted in these expectations.
If I had to make a comparison, would you expect a restaurant to send you a reply when you drop off a suggestion in the suggestion box? Microsoft, Google, or EA? The government? These entities have way more personnel and resources at their disposal. Maybe they would give you a canned response back, since they might have a dedicated PR or CM or other marketing person to return a pleasant non-answer.
Anyways, looks like this thread did result in action being taken regarding responses at the suggestions site so there's that. Someone should try setting up a suggestions subreddit. I suspect it won't gain enough traction to be superior than the current system though.
My 2c regarding the vote count - the whole point is to have users curate their own priorities, because the devs do not have the means to. If you've got 35 ideas and 25 votes, yes you have to remove votes from some of your own ideas, since the devs would never get around to 25 ideas from each idea filled person, much less 35. So the voting system supposedly encourages users to determine what is most important to them. If anything maybe it would be nice to add a some sort of policy where they reply to any idea with over a certain amount of votes, say 100. But the most likely response still isn't yes or no, it would be "Possibly, at an undetermined time in the future, should resources permit." Which is basically what the default response to every unanswered suggestion is anyway, and "Yes" wouldn't be an answer until it was ready to be pushed to beta anyway. Especially for big ideas like the scene graph that might take months of development. I would never say I'm working on it even if I decided to START working on it, because I don't know if I'd finish or how long it might take. Having an automated canned response of "Maybe" would likely do little to resolve the current frustration though.
They definitely used to read every suggestion on that site at least, regardless of response. I know some ideas with just a single person's votes had been implanted. There's probably fatigue over time with low quality suggestions, repeats, and sheer volume though, so eventually it would be taken less and less seriously or lower priority. That's why the occasional reset might not be such a bad idea after all, maybe annually with the top (5? 10? How many are reasonably expected to get implemented in a year?) ideas archived or carried over. Or maybe an idea expiration system, that culls ideas with less than x votes after y amount of time, but I doubt the platform supports that.