Looking for some exhaust advice.

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Hey all. I currently have a b18 swapped EF hatch. For exhaust i have the DC sports headers, a 2.5" high-flow cat, and 2.5 inc no-name brand cat back with can style muffler that was on it when i purchased it. I had left the 2.5" exhaust because i was planning on boost in the future, but now I changed my mind and decided that I don't need (and probably can't afford) the power and I'm aiming to just make a reliable daily / weekend autocross car.

Anyway, my exhaust is just way to loud and I'm looking to replace it in the future and had a few questions.

I'm currently looking in to getting either an ES oval and having a cat back fabricated or purchasing the Invidia N1 cat back. Would this quiet my car at all?
I was also thinking about dropping down to 2 1/4" piping. Would this provide any benefit? It's been my understanding that 2.5" piping is to big for non-turbo applications and doesn't provide optimal flow. I also figured the smaller pipe might quiet her down a little bit.

About the cat, Should i also look in to getting a smaller cat? Is the 2.5 cat if I get smaller piping for the cat back?

Anyone have any other advice or input?
a lot of people just use a standard 2.25" pipe with an ITR muffler.

I never thought about that. I might look up some videos when I get home and see how that sounds. How do they usually mount them under the EF? The exhaust crosses over and comes out the driver side. Is the ITR muffler short enough to fit over there?
crap, i just noticed it's for an ef and not eg. i'm not too sure about that. hopefully someone else who has worked on that platform knows a little more about it.
Its cool. I took a look at some pics online. Not sure that it would fit properly.
Appreciate the Input though.
For now I'm still thinking along the lines of getting a cat back made with 2.25 piping and an ES muffler.
On my old crx I had 2 1/4 inch pipe with a round magnaflow muffler as a resonator and a oval body magnaflow mounted in the stock location. It sounded pretty mellow around town but was still fun when you went out and ripped on it. maybe look into buying a nice muffler and a resonator and take it to an exhaust shop and have them bend up some pipes for you.
new muffler from dynomax called the vt series... check it out....
The Dynomax Super Turbo muffler should quiet it down; generally any chambered muffler would help out a lot.

If you're willing to buy a whole new kit, Greddy Evo2, SP2, and Apexi WSII are great sounding exhausts that are pretty quiet.

I have a 2 1/4" straight pipe with a Super Turbo muffler. So low and mellow below 3k but it can get loud when you're on it.

I would suggest a stainless catback, much better fitting and better quality.
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Thanks for the input guys. : )
That was the plan, to either buy a new stainless catback or have my mechanic fabricate one.

I'll look in to those recomendations and see how they sound.

Anybody have any input on the cat?
Should i leave the 2.5" or look in to getting a smaller unit?
Just leave the cat on(assuming it's fully functional)

2.5" will work just fine for a naturally aspirated engine.