Dark Room Mob Farm

Hi,
I have just finished making my first dark room xp farm.
It is just 32x32 and took me and my friend just over an hour to make but it is working pretty well and we plan to make it bigger. We decided to do this now that the mob spawning bug has been fixed and I am pleased with the output considering it is very small.
I based the design on this: https://www.youtube.com/watch?v=ldeas2i4R14 but I have adapted it slightly so that xp could be got from it. I have included an image and if anyone has got any improvements I can make please post

I suggest you should make multiple floors and a glass viewing platform above it. Thanks For Reading, Agent_Notch

I could do multiple floors but that would mess the falling damage up because some would fall say 30 blocks and others just 15 so some will die some will take only a small amount of damage.
I like the idea of a viewing area though

Is this open for anyone to use then? You have the Coords showing.

EDIT: I've replaced the image, thanks for pointing that out ChickZzHD.

I'm on the same server as you (I won't state it here), but can I use it please?

Sorry I don't want to share this with people I don't trust because it will end up getting griefed. I know that most people wouldn't grief but because of a small minority I cant publicly share this.

Oh well,

I know it sucks. I would love to be able to make a public grinder that anyone can help to build and use but on a public MC server it just isn't going to happen

I ran across and have been using a dark room spawner on Utopia. It is in a very public place. Cracks me up - because the people who built it have recently been banned as grievers. I would guess that makes is open to public use.

Lol thats ironic
Can you post some photos of it? I'm interested to see what other grinders people have made.