ok - first off, don't get lost in "wattage wars" - the speakers you can put in the front can only handle about 25 watts max, so anything more than that is foolish at best
as an audio engineer, i see this stuff happen all the time - people get caught up in the hype of specs, the sales pitch, too much mumbo jumbo from magazines, and end up spending way more than they need to - in the end they couldn't hear the difference in a car anyway
second - it's not about watts - it's about signal to noise ratio, efficiency, and tone controls that can adjust things for the cabin
third - steer clear of a graphic EQ with less than 15 bands - it just won't be able to do a good job, and end up muddying the sound - you want a parametric - there is a bit of a learning curve, but it is much more capable of tuning the car
if you are on a budget, go to best buy and have them put in a pioneer 4700 or better - it will run you a bit over 200 bucks installed - it will have a 3 band parametric eq, and an adjustable bass and treble that almost make it a 5 band parametric - this deck will put out 22watts RMS x 4 and be fully capable of powering the front and back speakers if you have a 6 speaker setup
i like the alpine line too - the alpine has more features, but a bit less power, and at more than double the cost - i opted for the pioneer because i did not want external amps - i have a 6 speaker setup and wanted to keep the weight down - i have no complaints - i hit over 100db clean with what i have - it's all about the speakers matching the power, and most importantly, good tuning
if you have more speakers than the 6 setup, then things are going to bet a bit pricier, because you would need to add amps
if you need more sub, things are going to get a bit pricier, because you would need to add a sub and amp, but that would only cost tops about $350 out the door
infinity reference 512i is a good replacement for the factory front speaker - leave the tweeters alone if they work - they are fine - the rears leave you some options - look for something that goes down to 40hz or so, and is set to operate in the 5-50watt range
all in all though, there is absolutely no reason to spend more than a grand on a system for this car installed - properly tuned, you can get every bit as much quality out of less expensive products
drop me an email if you are having a tough time - if you like, once you get it installed, if you come to the gathering this month in newtown, i would be happy to tune it for you