You went to the one place which we all advice against 
Anyways, all hope isn't lost. The jvc speakers you upgraded in the front can be moved to the back and you can get something different for the front (hopefully a pair of components)
If you dont want to add a dedicated amp, you need to look for some comps that can operate on low power and have comparably higher sensitivity
Again, if you don't want to add a sub (since you're not planning on adding a amp) might I suggest a small underseat sub. Trust me, makes a hell if a difference when you have a dedicated driver for the lows. They really blend in
Finally, the factory hobda headunit is fine. But installing a aftermarket headunit will allow you to tinker the sound staging and set different parameters which you can't from the factory unit. These are not expensive and the upgrade above will give you what you're looking for.
You can start slow and just upgrade the front speakers to some nice inexpensive comps first. Got the perfect candidate for that and the rest of the stuff.
Just give a number, the max you want to spend and let's work it out
