I found an ideal solution! (For me, at least.)
All I had to do was create RAM drives with the help of SoftPerfect RAM Disk. Now, with the way I'm doing things, everything (music players, audio files, etc.) is stored in memory, and no matter what I do, there is no stuttering whatsoever! Even with the processor-intensive HQPlayer.
Believe it or not, this also gives me much better sound quality than before. I'm freaking out at how much better all my music sounds now! There's a lot of info across the Internet about RAM disks sounding better, for those who care to research it without erroneously assuming it couldn't sound any different.
Update: Turns out it was only HQPlayer making the difference in sound. But I'm still gonna use the RAM drives to prevent stuttering and have much better playback of videos.
@Music Alchemist
Is there a RAM disk software for MAC?
Also, JRiver Media Center has a feature to load tracks onto memory, is this sort of the same?
Thanks
paul