I'm currently musically poor (rant)

[Gorille85]

i say listen to some unexpecT. but dont add em to your rotation...use em to replace metallica.

[Moonchild]

Everyone is putting their own favorite band indeed.

DT relates to Rush, Iron Maiden, Queen, Genesis, etc..
Megadeth relates to Testament, Judas Priest, Slayer, 80's Metallica, Exodus, Anthrax, Destruction, Kreator, etc..
90's Metallica relates to Alice in Chains, Guns n Roses, Red Hot Chili Peppers, Nirvana, Soundgarden, Pearl Jam, etc..

[Progmetty]

The couple "oh that's a nice twist" tricks The Unexpect have get really old really fast, to me.
Most of the other mentioned bands I've already been through, nothing exciting enough.
I got a couple of Devin Townsend albums, also debating trying more Symphony X cause I enjoyed Paradise Lost, the only album I have from them.
Never got into Rush beyond a greatest hits album that I found fun but wouldn't get back to it.
Maybe I'll give The Incident another try but Porcupine Tree is too depressing for me right now.
I know my attitude sounds spoiled but I'm just being honest with you guys.

[SPNKr]

Dunno, I've got a lot of music I could try running by you but if your favorite bands are Dream Theater, Megadeth, and Metallica I don't know if any of it would work for you. 

being stuck in a Dream Theater/Megadeth/Metallica phase for 4 years sounds like hell to me

listen to some jazz

Listen to something besides rock/metal. It'll be a nice change of pace.

John Coltrane

for Thrice.

Was in the same situation many years ago; this will get you through it:

1. Opeth
2. Pain of salvation



 

8. Devin Townsend


11. Between the Buried and Me

This music will challenge you to think and evaluate your musical tastes!

Ok if Opeth's vocals are a problem GET DAMNATION NOW

NOW. DAMNATION. DO IT.

If Thrice, Opeth, and Redemption vocals turn you off and you enjoy listening to Megadeth there's something wrong with you.

My advice would be to go outside of hard rock and metal, as Volk said.  Enjoy your pop and punk stuff, it can all be good fun!  And try some of these non-metal bands/artists:

Arcade Fire

The Decemberists

John Coltrane


And when you do return to metal, man up and love the growls.  Opeth's Watershed is how I eased into them.

[Dream_Theater01]

Alice In Chains

Perfect for any emotion or feeling.