I am on the same ROM, but I downloaded the full dandroid and just pulled out/put in what I wanted and needed, so I'm on a modified version of dandroid. No, you don't have to re-flash the rom to remove the call booster, all it does is add a file in a folder in system\etc called snd_soc_msm and within that folder is a file named snd_soc_msm_2x. You just need to replace this file with the original and reboot. I will give you the original file.
Also with the email- you do have to delete the email.apk and exchange2.apk or they will interfere with the email add-on. The email addon contains apks with the same file names that use the same system resources. They would clash. That part's not too difficult.
Anyway, I made a flashable zip to restore the original file and reverse the call boost. It's attached. If you want to swap out the files manually, I've included the file by itself, but please remove the .txt at the end or it will not work. Thanks.