You are right, you will have problems with the TXB0108 in your set-up, forget I recommended it.
I2C/SPI/UART and the microcontroller GPIOs were not designed to drive long wires/cables.
If you have connections longer than 1 foot you may have noise and/or signal distortion problems and you may need to do more than just level translation.
The level translator shown below is your best all around choice but you may need to add or remove pull-up resistors for best performance. For I2C/SPI/UART I would not use data rates over 100kHz with this translator. There should be no problem with the PWM 3.3V to 5V translation but add a 4.7K pull-up on the 5V side.