Vehicle Front Wing Design?

I have a buggy that has front braking only and due to its design can't be retrofitted with rear wheel brakes as well.

When sitting on the buggy the weight is over the back wheels and in braking there is not enough weight over the front wheel and so at speed the braking is not efficient - the front wheel locks up. No steering or stopping power which is a problem at speed!

To get a bit more down force on the front wheel I am thinking that a pair of front wings is the solution (pair - one on each side). Adding perhaps 10kg of down force would make the buggy a touch safer.

I have done some reading round on the subject and just want a few bits confirmed if that's OK?

The basic wing dimensions I am thinking about is going to be about 400mm x 200mm on each side. I am looking at a basic flat plate design for ease of manufacture (B&Q Can cut a piece of 5mm plywood to size, I drill a couple of holes and bolt it on) or a simple shaped wing perhaps with a 25mm or more leading edge

So here are the questions:

A. A flat plate wing could be used but a shaped wing looks ot be more effective. What sort of diameter curve should I be looking at making for the leading edge?

B. For both a flat plate wing and curved wing (assuming a simple curved wing with a flat top (upside down plane wing - for down force)). What would be a typical angle of attack for a wing 400 x 200mm?

C. What is the potential down force for a wing of this size and also what sort of additional drag would it produce?

Then of course, is there anything else I might like to know? Oh typical buggy speed is about 10mph

Thanks