For 6x9 coaxial speakers i went with pioneer 5-way, they are running off of the factory HU and its sounds really good.
Remeber that everybody likes something different in their sound. Some like mids, some like more bass others like more highs, etc. Go to your local audio store and listen to different speakers with a cd you like and choose the ones that sound the best to you.
As for the front the infinities are really good, i put some bostons FS60's infinity was my second choice if it were not for the deal i got on the Bostons. Don't forget to power those infinities properly If you have a budget and still want some good sound i would go with the
Power Acoustik OV2-520 and
4 Gauge amp kit By the way, wire is wire just name and outer insulation makes the difference.
Good luck