^^The way I look at it is that the SDCC figs don't prevent them putting those figs in sets, after all Green Arrow and Green Lantern were both initially SDCC exclusives. It's most likely lack of interest from LEGO's target market.
So the existence of the SDCC gigs just means that these figs do exist, even if I can't personally justify buying them .
Looking at the way the Superheroes themes have come on over the years I'm content with the variety we do get now.
I see no problem with this, the process to make the machine work takes not just creativity but also engineering.
Also LEGO's play testing often involves dropping models to test strength, and I've heard LEGO designers talk about being "initiated" by having to deliberately break models and break bricks so that they aren't too precious about their models.
I was told by one of the ideas team that they allow the crap models (like the one linked) so that the community are doing more of the selection process. So they no it generally has no chance of gaining many votes and will soon be closed - this is part of why they do the x number of votes in x time to stay in.
with that galactica project it's anyone's guess - are the helmets one from Star Wars? Clutching at straws but could be to do with that. might be that they don't want something micro fighter looking while the Star Wars ones are on the shelf?