This hero could be a support or main caster.
Q has a lot of possibilities. It's good burst if you throw all charges at once, it can be used to harrass, snipe creep kills, scout out enemies, interrupt channels and more, it's a simple ability with a million options.
W is quite possibly super broken. I still love it. The primary cast range is centered around your hero, the secondary cast range around the target. The secondary cast range should also be rather small (but not so small to feel useless). A way to balance this ability might be that it can only be used while the target is within the primary cast range. The applications of this ability are endless, so I won't get into it.
E is a mediocre disable but works well with the Q. Combo them together for very strong burst. The E should be somewhat hard to hit though. It can also be used to help whoever you are enabling with the R.
The ultimate is currently about enabling an allied caster. The values on it could be changed to be more about physical DPS if that feels better. I'm unsure if this should be self castable. If it can be it might force the hero too much into being a spell based dps and never be played as a support.
Overall I quite like this design.