First, how are you running a 690 with a VFD?
8250 is still pretty high for drilling. I'm using a Super-PID on a 690 and can drill at 5000 rpm.
If you need holes larger than 1/4", I'd just route them.
For smaller holes, Precise bits has 1/8" collets, and different size bits with 1/8" shanks. Precision solid carbide tools for woodworking and metal forming.