Full helmet (BMX) for Commuting, what is the current 2014 opinion? So, back 15 years ago, I think wearing helmet is kinda hype. 
I started wearing cycling helmet around 10 years ago seeing how dangerous cycling on the road is.

Just recently I got in an accident which I'm not sure what I can do better to avoid one (the accident) but to have more protection on myself.
The accident happened just when a young motorist decided to pulled out without any signal, checking blind spot and possibly mirror (I use Cateye EL-130, a warning sign 300 m away from me can still reflect my flaslight-strobing well back; a full Hi Vis jacket).

So when I was swerving, I lost balance and get thrown off the bike, chin and face planted on asphalt. 4 stitches on the chin, internal bleeding around the front teeth (have to take fluid for 3 weeks) and scar on face.

Enough with the accident background, my question is 
1) Would it worth buying a full helmet (BMX not motorcycle style) just to provide some protection, before my front teeth ever decide to part from me and my abuse. 
2) What is your thought being a cyclist, seeing another wearing full helmet on the road?

Side question:
a) Regarding the accident, was there anything else I can do, apart from riding on the very right edge of the lane (UK driving on left) and/or driving unacceptably slowly (less than 10 mph or 16 kmph) to keep control of the bicycle (and encourage motorist behind to overtake).
b) I am still hesitant to claim personal injury against the driver. Is there any advice? Looking for a solicitor I believe?

EDIT: Sorry I forgot to tell that I'm living in Scotland so temperature is not really a problem.. but I have never seen people riding full helmet on the street, lol. I think in here 50% people choosing not to have helmet, even worse...
EDIT 2: I actually mean this kind of helmet just to prevent some simple face-plant injury
Protection level is a personal preference matter.  You could just as well wear downhill style full body armor to commute and if you are willing to sacrifice the mobility and comfort for that extra level of protection, I'd say more power to you.  So my answer is you should wear whatever makes you feel more comfortable mentally.  The reality is it's all shades of grey.  If a one ton pickup hits you going 55 mph, there really isn't much you could be wearing that is going to do you any good.  I've been hit twice now commuting, but have stopped wearing any sort of helmet in the winter due to temperature control issues.  I value ease of temperature adjustment more than any feeling of safety I get from a helmet.  

So much of cycling is personal preference that I have seen several folks in town wearing full face helmets on what is seemingly a commute, and it doesn't bother me any more or less than the brand of bicycle they are riding.  

Edit:  I do not recommend wearing any less than the level of protection required by law in your area.  My jurisdiction has no such requirements.