That head unit is 14w per channel. If you're not going to run an amp to new speakers, then it's not even worth upgrading the speakers.
Just in case, if you can fit 6 x9s, you can fit 6.5s. There are going to be a lot more options with 6.5s. If you have the time, you should see what options you have. If you prefer components, that is the way to go. You're willing to spend a lot on 6x9s (that need an amp too), that you really need to figure out all your options before you buy.
If not, here are some 6x9s you should add to your list. I may just like Focal, but I would go with these over those other two with this deal.
<ul> <li>6"x9" 2-Way Coaxial Kit</li> <li>Power Handling:</li> <ul> <li>120W RMS</li> <li>240W Max</li> </ul> <li>Spider Decompression</li> <li>Kapton Former</li> <li>Tweeter Horn Cap</li> <li>Streamlined Grille</li> <li>Voice Coil: 0.375" High
www.woofersetc.com
Not sure what your rears are, but I would be looking for these with a 4 ch amp, 4x 120-125w RMS (with a very little give up or down). I know you can find amp and speaker options in that wattage range.