The most impressive performance change you will make to this motorcycle is the addition of the SuperTrapp. You can run this for a while before you have to re-jet the carb. Don't go too long, or your pipe will start to yellow toward turning blue. Starting at 6 discs is about right.
I re-jetted with the Dynojet kit, which gives you lots of jet options. After re-jetting, I moved out to 10 discs.
I clean and change the discs frequently looking for a combination that has the least black soot. I had the 10 discs for a while and still got some soot, so I went to 13. My spark plug looked very good at 13 but I haven't run the 13 long enough for another disc check.
The K&N air filter will give you noticeably more power at higher engine speeds when the demand for air is greater. Same thing happened when I put the K&N on my Miata.

You should be aware that your gas milage will decrease as you continue to chase more power. The best milage I got with the stock Savage was 46mpg. I ride only in town, no long highway runs. My milage after upgrades is about 42mpg.
After these changes, you will not be able to resist opening the throttle a lot more when an opening appears in front of you, so open your wallet for more rear tires and fuel.