Hmmm...
How long have you been playing?
I went like this for my electrics:
Ibanez GSR200 -> Modulus Quantum 4f -> Ibanez BTB1000 -> Modulus Vintage Jazz 4.
I currently have sold both Ibanezes, so I just own the Q and the VJ at present. I'm having a custom 4-string built by Carl Thompson (see
http://www.ctbasses.com and my thread in Other Instruments) which will more than likely replace whatever 4-string I have at the time of its completion.
I only really have a Daddy's Junky Music and a Guitar Center at my immediate disposal, and the selection between those two in boutique basses isn't that great. Guitar Center always has plenty of warwicks, but DJM is 80% Ibanez and Fender. When I went to guitar center, I found a used Quantum fretless. I knew how good moduluses were, and I knew that it was a rare find, and it was only a grand. I played it there, had them hold it, and bought it the next day. In this case, I loved the bass, and new it was a rare opportunity. That was probably in 2003 or early 2004.
So then, I had a high-end fretless and a shitty 4 fretted for a long time. I went to DJM and found the BTB1000 for half price at $800. At the time, I believed that with my skill level only allowed me to get a mid-range/quality bass, 'cause that's all I'd ever need. Don't fall into this line of thinking (though you're clearly not). Buy a bass that's going to make you want to play it 24/7. You'll get better faster.
So I ended up getting tired of the BTB, and bought the VJ on ebay for buyitnow $1200 through a guitar center auction. Then i sold both Ibanezes a little while ago.
Anyway... I guess what you need to do is try out as many things as you can. Read online reviews (bgra.net(com?)), vist
http://www.talkbass.com and post a thread there, do your research. If you're lucky, you can get the bass of your dreams on the first try, and you can focus on using your money to upgrade your rig. If you settle for something that's not quite what you want or what you love, then you'll regret it later and lose money when you have to replace it. Keep us updated as you narrow down your choices. Most of us can offer an opinion or two on lots of major bass brands.
Also... Carl Thompson is one of the more expensive... but there are luthiers out there who can build you a custom instrument for probably under your $2.5k budget. Darrin Huff isn't taking orders anymore... but watch his site (
http://www.dhuffguitars.com) for when he posts a new bass for sale. Mike Browne (
http://www.brownebasses.com) has worked with Carl and has a few basses available. Look on TalkBass.com for other custom builders, there are way more than you think. Email some builders, build some rapport with them, maybe make some connections. And have fun. Buying an expensive bass is exciting.