edit LV
If you are using the newer version of IR (14+) you should use this post.
Improved races aims to make the races more of a threat without changing any ship statistics. This is done through the use of items, new artificial intelligence routines, and...sometimes...overwhelming numbers.
Changes and download of r14 RC2 can be found in this post.
Requires:

AP Libraries SPK: http://www.filefront.com/14265253/AP%20 ... s%20r2.spk
AP Libraries ZIP: http://www.filefront.com/14265265/AP%20 ... s%20r2.zip
Download
Revision 13
IR SPK: http://www.filefront.com/14272411/Impro ... %20r13.spk
IR ZIP: http://www.filefront.com/14272415/Impro ... %20r13.zip
The racial improvements, sector takeovers and incursion responses default to off, you will need to enable them in the menu once you set you options up.
r13 Major Changes
New Option
Less Ships
You can now tell IR to make less ships to help with framerates and CPU load. This defaults to No fighters which will prevent non-Kha'ak counterstrikes and invasions from using fighters unless they belong to a carrier. You can also set this option to prevent fighters on carriers or allow fighters everywhere (Prior versions of IR allowed fighters everywhere).
Other Changes
1. Invasions tuned, the Xenon and other races should be a bit better now
2. Major bug fixed (I think) for those that went from r11 to r12
3. Several code optimizations.
4. Text file corrected.
5. There is less chance that a constructor will destroy itself when building a station now. The station itself may still catch on asteroids or rocks and get destroyed though.
6. Captured ships that were to be used in an invasion force should no longer behave badly
7. Several other minor fixes
Optional: Community Configuration Menu by Cycrow to use menus and configure options (The menu may also be accessed through the AL options).
Recomended: MARS Fire Control by Gazz...because I like launching missiles at you

Potential Conflicts: RRF by LV - This script is untested with and has had conflicts in the past with RRF. Some versions work perfectly fine though.
Minor Conflicts: Trancend 2 Mod - Economic boost option does not work properly and it is suggested you set this to off.
Uses text file: 8972
Uses piracy commands: 642, 643
Script Mirroring
Feel free to mirror this anywhere, but try and keep your mirror up to date

Script Usage
Please see the official post about using this script in your script package or mod. If you PM me with a link to your released mod or script package using these scripts I will cross link it here

Please post any bugs, feature requests, or comments.