Dissapointed with my new speakers

So a couple of weeks ago I replaced my 2 year old Klipsch RB25 bookshelves with a pair of B&W DM603 S2 floorstanders. When I first auditioned them I fell in love with their resolution and clarity however having lived with them for two weeks now, I am very dissapointed in the low-end and to a much lesser extent, the midrange.

On most songs, the bottom end seems very lacking compared to the Klipsch bookshelves and simply pales in comparison to the Klipsch RF82s we have in the living room. In addition the mid-range seems a little over emphasized. I can probably get used to the mid-range however, the lack of low end impact I probably couldn't get used to. I was thinking about adding a subwoofer but a half-decent one would start around $250 and go up from there and the speakers themselves are worth around $450-500. This got me thinking, maybe I should just switch to a different pair of speakers instead of trying to make the current system sound better. What do you guys suggest?

P.S.-I'm in Hawai'i so while I'm open to used speakers, shipping here will usually run about $250+ for floorstanders so I'd only have about $500 for the speakers.
>Also while pushing these speakers harder I found that they aren't very cohesive. I can hear the cross-over points for the woofer, the tweeter, and the mid-bass driver and they just don't come together smoothly, they sound like they're coming out of individual drivers (Which they are, I guess I just expect them to meld together better). Do you guys have any suggestions for better speakers? I auditioned a pair of Kef IQ90s and they sounded pretty good however I'd have to pay close to retail and was quoted $1100 which seems a bit much for these speakers.

With conventional speakers you need at least a three-way to get reasonable bass extension and output levels without distortion or polar response issues that make the speaker's performance very room+placement sensitive.

Parts cost on an unoffensive 2-way translates into ~$1K/pair MSRP through brick and mortar dealers, with a 3-way doubling the cost. You just can't sell a decent three way through conventional channels for less than $2K a pair.

The two-way one high and one low pass filter. The 3-way essentially has two high-pass filters and two low pass filters. The bass low pass and mid-range high pass occur at lower frequencies than in the 2-way so they use much larger and consequently expensive reactive components. IOW, cross-over costs more than double. Since little of the driver cost is in the tweeter (you see $25 tweeters on $8K speakers with $80 midrange drivers) and the bass driver requires a larger motor than the midrange driver those costs tend to at least double too, especially where multiple bass drivers are used to maintain sensitivity or provide higher output while fitting into an aesthetic narrow cabinet.
I would save up and find a used pair of Von Schweikert 4JR, they do what you want.
A word to the wise, you might stay away from Monitor Audio and be super careful of tweeter arrangement/design in any speaker you buy. MA speakers are incredibly bright (I owned two pair before). Great for home theater, brutal for music.

Textile dome tweeters may be more forgiving than metal dome in my experience, but regardless it's best to do an in home demo of at least a week to see if you can live with them. In store auditions are usually only good for an initial impression.
You might look at 2-way speakers with multiple woofers (2 or more).First order crossovers usually function the best at performing the task at hand.Seating distance can also be important in steeper sloped crossovers.
My experience with B&Ws has led me to favor the "Diamond" series,as they have changed to a 6db/oct crossover.
There are PSB dealers on Oahu (Elite Electronics, Honolulu) and Maui (Art & Automation, Wailuku and Maui Sound Systems, Kihei).

There is a Totem Acoustic dealer, Audio Lab, in Honolulu. If you want cohesive, Totem is a good candidate.