looking for a sound enhancement package for pmdg737 such as ground roll, reverse thruster etc

The default sounds for the NGX are very realistic. Any changes would be the opposite of enhancement.

Hello lad. I also find the default sounds of the NGX really good (don't own the plane myself, but there are no shortage of videos around), but, unlike a lot of people here on Avsim, I still remember that you are entitled to your own opinion (the horror!). So, if you are not satisfied with the default sounds of the NGX, take a look at these topics: 

 

http://forum.avsim.net/topic/406453-pmdg-737-ngx-soundpack/

 

http://forum.avsim.net/topic/450123-brand-new-ngx-groundroll-enhancements/

 

Just remember to backup the original sounds, in case you want to get back to them ^_^ .

 

 

Cheers!