What was the sleep citadel like? (or whatever it was called)
The Shrine of Slumber was actually a really cool set of levels.
The tileset was the same as the night-time Aurora Isles ones.
But it had the Blue Lichen in it.
Generally Sleep wasn't a threatening status. As long as you had a gun or a bomb to stay out of the Sloombargo's sleep dust you were fine.
But it had some really nice gate puzzles in it.

I get the impression that there were a lot of big open spaces back then (like the BN prototype) Would you say things since then have trended towards smaller rooms?
I think the removal of a lot of the old pre-fabricated levels in place of adding more themed levels made the levels seem more claustrophobic by adding more hallways. But I don't really remember the game trending towards small spaces. The level designs are usually pretty well paced in that regard.

Did you ever get a Zee core?
I had quite a number of them in beta.
I don't have any now, though.
Not that they were ever used for anything.

Was Super Brawl redundant, or were there any gimmicks like respawning monsters? Was it as overly competitive as Lockdown?
People boosted for the lower tier Brawl Crowns since there were hardly any players back then.
There was an event with monsters in it that ran before the beta ended.
I would call Super Brawl redundant, simply because of the amount of damage you could put out with shield cancelling and such.
Gran Faust was the Tip-Top Tier back then.

Was the Tortodrone really too hard for T2 players?
No.
I think they removed him because he had a passive AI. People would see it on screen and panic and attack not knowing that they didn't have to and get stomped by it, since it looked like a sub-boss, considering it's size.
It will probably reappear with the only thing that made it unique removed, to make the game more friendly for idiots with too much money.

Were bombs like how they were in the trailer, with no charge time but a smaller radius?
Yep. That was before the 2010 beta. Back in late 2009 I believe?
You could drop 3 uncharged bombs or 1 charged bomb at a time.
Fun, but not too balanced, I suppose.

What was it like with no binding/Auction House?
Fun. But too easy.
Infinitely more Pay-to-Win than it is now.

Were Vog Cubs any different from normal Wolvers?
They were basically Ash Tails that could set you on fire, from what I remember.

What were Menders and Devilites like back then?
Menders were basically D&D Clerics and Devilites haven't really changed too much.

Why did they get rid of the Sleep levels entirely without just removing Sleep and replacing it with Stun or something for the time being?
Probably because sleep wasn't all too threatening.
Or they want to bring it back, but they don't know what to do with it.

How did Basil work before he appeared in terminals?
In the 2009 beta, he sold High-Tier items for 800cr.
Specifically the Silversix, Graviton Vortex, Divine Avenger and Gran Faust.
As well as Silver Keys, which were used to open Danger Room and Treasure Room gates back then, instead of CE.
But they took those out too for not being user friendly enough.
Before the official release you could invite people to Basil to buy certain recipes.
They removed this with the binding update, I believe.

Is there any hope for difficulty to exist again, do you think?
If they remove CE revives and nerf heart trinkets... Maybe.

What were the gold turrets and trojans like?

Completely invincible and really cool.
The Gold Trojan was in a gate puzzle where you had to get a Gold Key and he would hit the gate switches to bring the gate back up while you were trying to pick up the key.

Were bombs usefull?

Yeah. They were actually pretty good.
The one thing I liked is that you could use all three weapon types and none of them really felt overpowered in comparison to another.
Because there were no equipment bonuses or anything.
And you could drop bombs without the charging.
Guns just made it really made it easy to get through fights without getting hit because of their stupid range.

How did Tordy fight like?

He had a Shoryuken, a ground smash and fired a bunch of missiles in the air that marked dots on the ground before they landed, then stayed stuck in the ground and could stun and shock you. The downside is that Tortodrone could damage himself with the shards so you kill him without hitting him.

How sustainable was CE back in beta/very early release (i joined 2 months or so after release)?

Hardly anybody played, I think nick said there was only a few hundred people in the early parts of the beta.
So CE trading happened usually through stuff like rare equipment and materials rather than actual crowns.
I just remember all the buy offers being somewhere close to 2k and all the sell offers being 10k+ and nobody trading anything using the exchange until they made all of the changes to binding and crafting.

How did you entertain yourself before bosses? I get the feeling endless clockwork runs would have gotten old fast.

Not really. The levels themselves were all unique and they had a fair few secrets in them. Plus there was the rare spawns that dropped items you were always hunting for. It's kinda stupid they made both the rare monsters rare then put no items in them or make the item drops just stupidly rare to boot. Kinda ruins half the point of rare monster spawns when you only get a measly 50cr 99% of the time.
Aside from that, I think Vanaduke was in the 2010 beta from the start, just nobody could really beat him until later on. Or we couldn't make gates that reached the lower strata until later on in the beta but he was always there. I don't really remember.

If there was one addition you would like to see in the game, what would it be?

A lot of the things I wanted to see added to the game got put in already. I suppose, if anything, I'd like to just see them doing something that makes sense.

Any particular features you miss?

I miss the old Silver Keys. I thought they had a lot of potential in regards to creating alternate routes through levels.
But I guess we'll never see anything cool like that again.
I also miss the days when Divine Avengers and Gran Fausts didn't exist outside of recipes and then the days where they existed only as extremely rare drops.
They were kinda like the Darkfang Shield in that regard. Just you had to also find the recipes to upgrade them.