I actually quite like Temporal Anchor in that it is what makes Protea unique. On linear missions when speed is of the essence is isn't very helpful, of course, but at other times it is nice that it rewards forward planning as, when thoughtfully placed, it can be a very useful repositioning device or recall point. (My current lich is probably well sick of it by now!) Running lich missions and not getting anyone join - as is sadly too often the case - I also found it great for marking a safe point, diving into a particularly dangerous room then winding back. It has great synergy with the Twin Basolk's rift strike too - either for in-and-out strikes or, if timed correctly, preventing relocation due to rewind. Perhaps some options on cast; say, tap to have echoes catch up as per anarchy753's suggestion above and hold to rewind after the duration as per current?
For a time manipulation frame, however, I would prefer her other abilities to be more time-y rather than Vauban 2.0. At the moment she seems to have a rather confused identity. Working with them as they are, however:
Her 1 is difficult to aim and, while the alternate shield option is very handy, it would be less clunky if it were applied directly to the squad rather than having to be picked up (plus wondering if the desired type registered correctly). The damage option isn't that strong, either.
Her 2 is a decent idea but needs serious buffing in terms of damage and duration.
Her 3 is OK - but still outclassed by Wisp's 1, so very mediocre for a 3rd ability with the associated energy cost.
Alternatively go for 3 more time-y abilities, e.g. one could be something like 'borrowed time' - release an outward wave that slows enemies and accelerates allies caught in its radius (or as an aura following Protea), either wholly or partially such as fire-rate, so it sits neatly between Volt, Nova and Wisp's similar abilities while maintaining its on distinctiveness.
Or if you wanted to do something really cool, give her one 'time travel' type ability - such as her current 4 - then make 3 other time-y abilities that have their own effect, but when used in conjunction with the 'time travel' ability gain additional effects based on common time-travel concepts, e.g. chrono-cloning, paradox damage. The more abilities (and which ones) you combine during your 'time travel' duration, the crazier the added effects. Also because the additional effects would be delayed, the player would have to plan ahead, making a frame that is tricky to master but powerful when you do (and probably suited more to higher-level missions where enemies aren't already dead from squad-mates) - or just give the added effects immediately, a bit like Gauss. If power-limitation is needed, the player could take self-damage/self-stun from the paradox caused by combining too much too much while time travelling.