Fresh off a level 4 playtest this evening. Here's my experience playing the witchwarper.
We played with Free Archetype. I played a Ysoki (Borai heritage), Gap-influenced paradox with the Focal Point anchor. My chosen archetype was Psychic, with the Unbound Step mind (selecting Warp Step as the cantrip).
I had Quantum Pulse, so I did get to set up the field immediately, but that also meant it began taxing actions immediately. My anchoring spell is a (great!) reaction, so it can never help sustain the field. The field wants to be on enemies so that I'm concealed from them, given that this is meant to be a ranged game. However, that means that my signature spells can't gain anchoring to help me maintain the field, since I do not want to cross the battlefield to stand next to enemies as a relatively fragile full caster class. As a result, enemies rarely attacked me at all, preferring to target the easier soldier and solarian targets nearby. This meant that the only benefit I received from my actions maintaining the field was the ability to cast Warp Presence, which *is* a good spell, but is only one of many.
I also had issues making use of my chosen feat Scrub Psyche; even when an ally was Dominated, they weren't in the field, so I needed to spend effectively my entire turn to Dismiss the field and re-open it under them, and then pray that they remained within the minuscule 15-foot burst at the end of _their_ turn when they made their Will save. Maintaining the field is annoying and the payoff is ultimately not worth it, but without the field I have basically no class features except being a spellcaster. I think the feats that make the field less painful to use, like Quantum Transposition and Enlarge Quantum Field, need to be seriously reconsidered as feats rather than features, and the field needs to be impactful at a level earlier than 8.
