Free flow exhaust
Instead of installing air intake. Simply remove "Air resonator box" located in between passenger side tire shield and front bumper and extend the pipe to where resonator box is located. You will see improvement in response of car and sound on high RPMS will be like a long ram intake. But your air filter will get dirty more often so get it cleaned after 3-4 days from service station guys. Use synthetic oils for better response
Brakes are fairly good enough to even stop a swapped k20A civic. So I guess you won't be needing to spend on brakes.
Google Unichip pakistan. They claim to draw out 20 or more hp from engine on stock settings.
This is all what I have plan to do. Already went for exhaust and removed Air resonator box and soon going for Unichip as heard a lot about them.
Rest you can visit 8th Generation Honda Civic Forum. There is a lot of stuff for R18A engine and regarding your query over there.