I think PIC12F675 and PIC12F683 are both quite antique devce types,
and awkward for experimentation and development.
They cannot be debugged in hardware (without a debug adapter), and have small program and data memory.
There have been a lot of development in the meantime.
Newer device types can be debugged in hardware, even som of the small PIC12F in 8 pin package.
PIC12F1822 or PIC12F1840 can be programmed and debugged in MPLAB 8.92,
but will need PICkit 3 programmer tool for this.
For learning and development, I would suggest PIC16F1824, PIC16F1825 or PIC16F1826 in 14 pin package,
or PIC16F1828 or PIC16F1829 in 20 pin package.
These microcontrollers have internal oscillator with PLL, and are able to run with clock frequency up to 32 MHz.
When you understand what you do, and have code that work, condense it into a 8-pin device.
All these devices are pin compatible, 8 pins at end of the package, with PIC12F683.
Jitter may be reduced by averaging or hysteresis in software.
The latest development in this line is PIC16F18323,
but then you will get PPS pin remapping, which may make code setup a little more complicated,
and will have to learn to use MPLAB X for development.