Fixing a speaker I was sold... Focus / Audax components... how to proceed?

Hi all... I think this is my first project around here, so I hope I don't make too many mistakes... please bear with me while I learn. I promise to try and not to make many stupid questions :)

This is the second loudspeaker I'm attempting to build. The first one was Zaph's wonderful 3" Hi-Vi project, which I feel is an excellent first time project. It taught me lots of things I didn't know about.

Here's the story. I bought a pair of loudspeakers from a designer around here. He used the following drivers...

Audax TW034X0 - A 1 1/2" tweeter.
From what I understand from the frequency response graph, its upper frequency response tops at around 15 KHz. :(

JMLab Reference 5 NV 4211 woofer (2, D'Apollito configuration).
A standard woofer, with an FS of 42Hz.

Anyway, the speaker, to my ears, sound awful. It has no detail whatsoever, and I need to raise the volume a lot in order to make it come alive. It also has no real highs to speak of.

Now, I'm wondering how to proceed. The speaker does have a midrange to die for - absolutely great. So I guess I may want to keep the JM's.

I'd suppose the fact that this speaker needs a lot of power in order to hear the details may have something to do with its crossover topology (too complex). AFAIK, the speaker has a 1st Order Crossover with impedance equalization.

I also wonder whether it has a padding resistor in the tweeter that has too high of a value.

I'm thinking about buying X-Over 3.0 for this project. I use TrueRTA and my laptop for my current subwoofer projects.

So, I'm thinking about modding the speaker in 3 phases.

Phase 1:
* Verify and modify the tweeter padding resistor (if one exists).

Phase 2:
* Rework the crossover topology using X-Over 3 into a 4th order crossover (I'm not sure about this point. I understand 4th order electrical, but apparently I also have to consider the roll-off properties of each driver... I'm confused!).
* Replace the tweeter with a more detailed one, with a higher frequency response (I'm thinking about the new Dayton Reference aluminum tweeter - it looks very good), if necessary.

Phase 3:
* Rework the cabinet, and build a floorstanding tower with the reworked tweeter, adding a bit of bottom end extension.

Phase 2 worries me a lot. That's why I'm thking about using X*Over 3. The thing is, I don't think the software has a Baffle Step Compensation option, so I'm not really sure it's that useful.

I might wonder why on earth I'm going through too much trouble to fix something like this... the answer is, those speakers were awfully expensive, the drivers seem to be good quality ones, and, since I already paid for everything, it could be a fun, rewarding project on the cheap.

Thanks for all your help... and I sure hope there's not too much information for a first post ;)