Comma Paradise hehe, sorry: It may not mean much coming from someone as young as myself and who hasn't been listening to DT for as long as most of you probably have, but it may be just as interesting for some veteran fans to read my opinion as it was for me reading yours.
I started listening to DT about 3 years ago at a pretty pivotal age for discovering yourself in music and interests, and for that first year, I only listened to them. Seriously. I was familiar with some Prog through my parents and was and still am a fan of a few big name Prog rock bands that probably don't even need to be mentioned on this forum to be recognized, but Dream Theater was my first foray into Progressive Metal. And Jesus Christ did they kick my ass that entire year. I was always a huge Thrash Metal fan, and it's still my favorite genre, but there was something magical about this band. I always knew there was something about them specifically that was special, but despite them solely dominating my ears for a lengthy period of time, I always accredited the entire Progressive Metal genre for being my affinity.
After I had finished remembering all parts of their material by heart, like I'm sure the great majority of you have, I started to go back to my other musical loves, mostly metal, but fairly vast. If it may help you understand my perspective a bit more, I try to listen to everything except Country, but Metal happens to enchant me in an indescribable way, with Thrash being my favorite because of the VAST amount of talented and amazing bands out there and Dream Theater being my favorite band because... Well, you should know hehe. Anywhoo, after a while, I decided to give the genre that I had thought to be so amazing (because of one band) a chance by actually listening to not-Dream Theater. I started off with Redemption, Fates Warning, Symphony X, and other name Prog bands, and while there was some great material there, I always found myself bored. I felt exactly the way you did, and everything really paled in comparison to DT or sounded like a watered-down/try-hard version of them.. It was a weird feeling, but I never really lost faith in it, especially since
I still had my taste for Classic Prog.
The first Progressive Metal band to grab me in any way for a while was Pain of Salvation. I had heard wonders about them, but was iffy since I had heard that they were more "Prog Rock" but not "Prog Rock", and wasn't sure what to expect. Now, I play guitar and we guitarists like to think we have an easier time understanding music that's new and different to the normal ear, and I have looked to DT and JP specifically as big inspirations on my playing since I listened to them and figured my own style yet, but I think that it was with PoS and looking back at DT, bands I had checked out previously, and classics like Yes and King Crimson that I REALLY got and learned what the Progressive genre was. I listened to The Perfect Element and was blown right away. Here was this Progressive Metal band that had really interesting instrumentation like DT does but in a different way; they weren't really as flaring and flashy as the Prog that I had heard and thought the genre confined to be. Everything they did was different, more than just a specific band or genre influence. Here was a singer that wasn't just roaring, soaring, or singing his ass off, but doing some crazy weird shit with his voice ala Mike Patton (on A Trace of Blood in Remedy Lane, he scats! definitely caught me off guard in a good way!) and doing other innovations like DT had with their music, but obviously in other ways. Here was band who, aside from the first few albums, didn't have a definitive sound as much as definitive elements. It opened my eyes in seeing the genre - understanding Progressive music as a whole, not just as being experimental like PoS or sounding like-DT and/or Rush.
From there, and for the most part of the last year and a half or so, I've been getting REALLY into the Prog scene, from Prog Rock like TFK and Moon Safari to Neo-Prog like IQ and Arena, and other examples that may be known around the forum. There's just so much you can do, so much that can make a song Progressive. To me, there's this almost euphorious aroma of mystery surrounding a new band or something I haven't heard yet because you never know what you're going to get. I mean, sure, there are a lot of DT-clones and bands labeling bad Tech Metal as Prog, but finding a band like Haken or Canvas Solaris or w/e that really captures that respective sound well is crazy. And even then, such as in Haken's case, aside from a few sections throughout Visions, their sound is very distinct in comparison to Dream Theater's and other bands.
Thrash may be my favorite genre, but it's only because of the sheer amount of good Thrash bands that are out there. Prog has maintained a strong 2nd spot for me because of how spectacular it is when you do find a good band. And it's not like there aren't a lot - because there are. It may not be your thing, and I understand liking Prog and not DT because Dream Theater is a band that has been comprised of musical angels, but as possible with every genre, if you look really deep and find that majesty and connection that separates itself from DT(which of course you may never do, which is A-OK), you'll find a pretty wide gold mine. And judging from the songs I heard from some of the fairly large haul of new bands and old I worked my ass off to order from LaserCD today actually, if some of you ever do get to embrace Prog, you can, and always will be able to find yourself a lot of good material.
TL;DR - I fuckin' love Prog and I hope you all do one day too