Is there any way to change the game speed aside from the slow motion option that's given? Default speed is too fast for me and slow motion is too slow so I'm wondering if there's a way to adjust the game speed so that it's somewhere in the middle (or maybe just slightly slower than default).

If you're asking about Jazz 1 and you're running it through DOSBox, you could try configuring the cycles: https://www.dosbox.com/wiki/Performance