What should i do to my accord ?

Should i lower it? or should i put a cat back exhaust system? 

Yes. and yes.

Now it is up to you how aggressive you want your car to look. big drop and 2.5 catback vs. tasteful 1-1.3 drop and 2.25 custom sp2 or ws2 or tanabe catback

for the record, i had so much more to post. FREAKING HAF SERVER/SOFTWARE irritates me to no bounds.