Suggestions on XBLA games?

I was given a 4000 MS Points card recently, and I'm trying to find something good to play. I'm not going to buy any more TV shows or rent movies due to me getting tired of videos dominating my hard drive. So does anyone recommend a Live Arcade game that's worth downloading?
 
And to avoid anyone recommending something I already have, here's what I've got: (In no specific order)
 
Vandal Hearts: FoJ
Sam & Max Save the World
Joust
Missile Command
DOOM
Wolfenstein 3D
Monkey Island
'Splosion Man 
Braid
SoulCalibur
MS Pacman
Portal: Still Alive
Penny Arcade Adventures (Both)
Uno
The Dishwasher
Wits & Wagers (don't ask...)
Scrabble & Yahtzee (Needed something to play with the Ex)
Sonic 2
Geometry Wars
N+
Marathon: Durandal
Castlevania SOTN (First Arcade game I bought)
DIGDUG
...I may have 1 or 2 that I forgot about. And I have the demo for Trials HD, which I'm not sure about. The demo isn't really helping me determine.
 
I'm going to buy Perfect Dark next month. But I need something to hold me over in the meantime.
 
Update: Forgot to mention that I have Shadow Complex already. Got it when it was released. Oh, and Castle Crashers.

Geometry Wars 2 is great to play at times. Shadow Complex is great. 

Puzzle Quest: Challenge of the Warlords
Pacman Championship Edition
Rez HD

I second Shadow Complex and Darwinia + is cool imo. 
 Also Duke Nukem 3D, that is if you enjoyed Doom.

Shadow Complex or Puzzle Quest are solid choices.

Shadow Complex is fucking great. Get it.

shadow complex and battlefield and duke nukem

" Geometry Wars 2 is great to play at times. Shadow Complex is great.  "

" Braid, Duke Nukem and Battlefield are all awesome.
 
And remember to keep some points for Perfect Dark that will be coming out next month in March!!! "

shadow complex, and don't forget about castle crashers, especially if you have friends

shadow complex or castle crashers

" shadow complex or castle crashers "

" shadow complex, and don't forget about castle crashers, especially if you have friends "

" @Bubahula said:

" shadow complex, and don't forget about castle crashers, especially if you have friends "

I have no friends........... But yeah, I have both. "

Woah!? Where is the Marvel vs. Capcom 2? That game is AmaZinG!!

 Splosion Man, Sonic 2 and Portal: Still Alive our my pics from your list.   But if you have the Orangebox don't buy Portal its already on that.
 
Also Indy game called "Yet another Zombie Defense" is amazing and only $1.

Pick up some indie games. I highly, highly recommend the Arkedo Series, very high quality games (and only $3 apiece).

For the love of God, Shadow Complex dude.

As other people have said I also would say Shadow Complex because its great. Also, you might want to consider Castle Crashers because its pretty good too.

Trigger Heart Exelica, Ikaruga, Space Invaders Extreme. These games have the highest replay value to me, I can play them over and over just trying to get a higher score.

Duke Nukem and Geometry Wars. I was going to say the Perfect Dark Remix but you already got that on your list.

Trials HD, man. 
Simple to learn, super addictive... 
SADISTIC difficulty in the later stages.  Perfect.

" @dantheman1515 said:

" Geometry Wars 2 is great to play at times. Shadow Complex is great.  "

I knew I forgot something. I have Shadow Complex. "