1) Your swing isn't crappy, you haven't been playing long enough to groove it, so it isn't comfortable. Use inconsistent instead of crappy, breaking par is not crappy.
2) You said "....I need to cock my wrists and I seem to be quite literally overdoing it" You are creating lag. Depending on who you talk to you can not have too much lag, more lag is more power.
3) You said "As a result I am unable to get the driver back to parrallel without bending my left arm...." Firstly, the driver does not need to reach parrallel, and secondly, a slight bend in the left arm will return to straight or extended by impact. This is due to the effect of centrifugal force, if you believe in centrifugal force...
4) You said "I frequently go past parallel though with this as I lose all sense of where the club finishes its arc when loading." You might already know this, but try squeezing the grip a little tighter with the last 2-3 fingers of your left hand (for a righty, the pinkie, ring and middle fingers). If there is one spot where the grip is 'tight' or 'firm', it is in these fingers and the edge of the palm, which secures the handle of the club (so you don't 'lose all sense of the club'). I believe #4 will help you successfully imitate the feeling you are searching for.
5) Like someone said earlier, a full length mirror can wonders for your game.
6) Relax and don't go crazy...if you are a legit 4 after 15 months then you are miles ahead of basically every single person who takes up this grand old game.....and if nothing i've said works out then enjoy the fact you played recently, I'm gonna shovel snow when I wake up tommorrow.
Good luck, play well