The simple answer is:
Q: How should #askhubski be substantively different from Ask Reddit?
A: There should be no #askhubski.
There will be/is no "whole Hubski." The entire idea of Hubski is that if you and I are part of completely different worlds and hate everything about each other, we will very, very rarely interact. Never, ideally, and if ignoring works as it ought to.
The idea of AskReddit is that you want to get people's opinions on things, or stories from people who interest you. Maybe you like hypotheticals about super powers, maybe I like stories from people's lives, maybe @mk likes questions about how cool space is. If we use Hubski as it ought to be used, as a series of diverse and interconnected communities, an ocean carefully sorted by the centrifuge of shares into an organized series of like-minded or similarly-interested people, then you'll be able to ask exactly the people whom you would most want to hear answers from.
If you like people who talk about hypotheticals, you'll follow them. And if I like people who tell stories, I'll follow them. And if we overlap, then our interests somewhat overlap! Otherwise, I won't ask you questions. And that is awesome.
Think about Hubski as high school. Not Hollywood high school- actual high school. Sure, you had a close group of friends you could talk to privately, and yes, you got all of the important gossip about a larger group of people, but did you ever really want to know if the second-string baseball player got the prom date of his choice? You didn't. Nothing against him, but unless you sat next to him on the bench or in class or on the bus and liked him, you just wouldn't care. Even if it turned up in conversation you'd think "huh. okay" and move on, and never talk about it again because you weren't interested.
That's what Hubski is. I like hanging out with the mods and the poetry people, and some people really like the programming tag, and I have some friends who like the programming tag because we both have #philosophy at the same time and we're interested in why kleinbl00 is always angry. But if your question is "Why are the Patriots So Bad This Year?" I honestly don't care. And I will not care. And if it pops up on my feed I won't share it, and I'll block the #sports tag if it gets bad. Nothing against the post. I just don't care.
In a very real sense, there is no Hubski group. The site is designed to avoid a hivemind in place of a clique attitude- no set boundaries, but definite and tight communities with a million ties to one another and no clear delimiters. So what should you "ask hubski?" Nothing! You should ask your #imagination friends what useless superpowers they want, and I should ask my #hubski friends why we don't have an easy way to block tags only from specific users, and if you're not interested in anything I'm interested in you'll never have to hear about my boring stories on the bus about this one cheerleader I love, because you and I won't interact! And if I'm constantly talking about board games and you don't care about board games at all you can eternally silence my board game chatter and still be my friend. And I will never know or care and I'll do the same to your sports!
Imagine instead in high school that if you were taking a math class, then every time someone had a question in any math class in the whole school it would be said into the PA in your room. How much math do you think would get done? That's what organization by subject instead of by user brings. And #askhubski is that, but for every question in every class in the whole school. Sure, it might be interesting to some people, but if everyone likes a question then everyone will be "talking about" (sharing) it, and we'll all hear about it. Hubski's sharing is word of mouth made into a website.
That said, if you're friends with a bunch of people who love the idea of asking hubski stuff- AWESOME! But the second I get bored of you guys, I'll just ignore you. And if I ever wanna phone up and see how you're doing I'll search for #askhubski
Don't Ask Hubski anything! Ask your friends!
PS-Congrats about the cheerleader. Seriously, dude, she's so hot and it couldn't happen to a nicer person. Do you think your parents will mind if I have some soda while we play PS2?