I think if we do a 6-monthly reset, we could take the top 10 or so ideas at the end of that period, and permanently archive them somewhere, so the fact they got a lot of votes is recorded and isn't lost right away.
The whole point of this discussion is to figure out how to avoid people inundating us with a mountain of work that is literally impossible to implement. Then people get disappointed that what they suggested isn't being worked on. If people can post unlimited suggestions, we'll be inundated. If people can have unlimited votes, then one person can vote on an impossible amount of work for us, and they are guaranteed to be disappointed. If ideas are left behind forever, then gradually it builds up to an impossible amount of work.
So I do think that if you want to avoid disappointment, then we need limited idea submission and limited votes. If you are OK with being disappointed, then the current system is working fine. But the general view here is it's not working fine, which is why we're having this discussion. We probably need to make a significant change. If you want to post 100 suggestions, I can see how a system that resets every 6 months is annoying. But it's more realistic. It's probably far too much work to do all 100 ideas that you want to submit, especially taking in to account all the other ideas other users are submitting. So resetting the system acts as a filter. If you are willing to keep reposting your ideas, then it's another signal it's something you really want, rather than a throwaway idea someone made a couple of years ago but nobody really cares about it. If you know the ideas will all be deleted in 6 months and so you post your top 10 ideas instead of 100, that is actually much more useful to us.
I get that Scirra can't make accurate judgements on the feasibility of a new idea, but if that's the case, then ANY method of handling suggestions is fundamentally pointless
No, that's not the case. When we take on a big feature, we both investigate the feasibility and figure out what it will involve, and plan assuming there will be unexpected complications, follow-on feature requests, and a long tail of associated bug reports. The problem arises when we think something will take say 2 days, and it ends up taking 2 months when we never planned for that. We'll have full-time work already lined up for those 2 months. So then we end up with the stress of unexpectedly having more work than we intended, and other projects get delayed or postponed as we scramble to sort out the things that have gone wrong.
On a positive note, there are lots of big improvements that came from the suggestions platform. For example, I doubt we'd have done the scene graph feature by now, without having a user submit the suggestion and lots of other people vote it up in to one of the most popular ideas. Taking that from initial design to completion was about 6 months though, and when starting it, I expected it to take about that long. So naturally we can't exactly do that every day. But the fact lots of people voted for it was a useful signal to us. That's the main purpose of the system: it's a way to give us feedback on what most people want.