XRAY - Model racing cars

What's the best way of gaining front end grip

As I was told, sometimes you need to look at the other end and take away the grip from their, in your case the rear.

but you could try softer front shock oil.
Stiffer rear roll bar/softer front roll bar
Stiffer rear springs/softer front springs.

Front steering brace

Normally the tyre´s changes is what more affect. Shocks second, and transmission third.

Front camber/less rear camber
Front lay shocks
More coastal says

I think you have understeed. Try to softer the front rollings parameters.