Upgrade questions

Hello, I own a 2007 Impreza 2.5i with only 110k miles. I was looking to upgrade my car performance wise and was wondering where to start. From various sources, I was told that coil overs and cold air intake were among the best to start/begin with. Thoughts or concerns?

What you gain won't really be noticeable. The 2.5 really can't improve unless you spend lots of money. ie Turbo