Fretless bass emulation is a tough one in the H9. I have some glide presets for the PitchFlex algo, but the results sound decidedly synthetic. There's no way around the fret increments when you actually do glide. .
You can get the characteristic 'softened attack' of a fretless with the UltraTap algorithm. Set the Mix to 100, and most everything else to 0. Then start out with the Swell [CHOP] at 5, and the RISE time between 10-30. Between the PitchFactor [PitchFlex] and the H9 [UltraTap], I can approach a fretless sound. It's more like a synth trying to fake a fretless.
Let's hear some more about your phase / flange experiments. I've never gotten an exact emulation, but Mutron-like effects are relatively painless. Most algorithms with envelope control have similar parameters, so presets are transferrable across phaser, flanger, filters, etc.