I have a giant fastroad e+ ex pro and was wondering if there was an easy way of adding an additional brighter front light?
How bright would you like? It would be easy to overload the lighting circuit of your bike's propretary controller by adding even an equally useless light to the one you have, plus you run the risk of your propretary controller signalling an error, which may require servicing or repair. You're better off with a separately powered lighting system. I went from this connected to my Bafang BBS01B mid-drive controller, which might be as useless as your headlight:
https://www.pswpower.com/products/electric-bicycle-ebike-downtube-spare-ebike-battery-36v-10ah-bottle-electric-bicycle-battery-pack-fits-350w-bafang-tsdz2b-motor-330
...to this:
...and I did so because in my experience no cyclist is assured of safety on the roads these days, even with lights appraoching or exceeding the level of illumination motorcycles provide, continuously on day and night in flashing or constant modes respectively. Another thing to bear in mind is, powerful lights connected to your ebike battery (if possible) will impact range - mine do, but happily I have a 19.2Ah/691Wh battery. In total, my lights draw about 1.95A from my ebike's battery, 36V X 1.95A = 70.2W. Sadly ebikes don't have alternators powered by petrol engines to power motorbike headlights (this may well be the future), but you you could buy an ebike bottle battery, and connect/solder lights to it via a blade fuse (or three, to increase the odds, because blade fuses don't always blow) and a waterproof switch on the handlebar.
https://www.pswpower.com/products/electric-bicycle-ebike-downtube-spare-ebike-battery-36v-10ah-bottle-electric-bicycle-battery-pack-fits-350w-bafang-tsdz2b-motor-330
Alternatively, search the information superhighway for brighter discretely powered bicycle headlights. The very bright ones with their own batteries I've seen are expensive, will dazzle drivers, and look wholly unsuitable for road use. Beams are too wide and not adjustable. My three headslights and fork light combined, illuminate the road surface ahead at night quite nicely, without dazzling, casting a combined beam long enough for fast riding at night or slow. Plus I'm always noticed by drivers day or night. It's hilarious my being mistaken for a motorcycle approaching from a distance - drivers now wait ages at intersections for me to pass by, only to see me pedalling past slowly at a mere 15.5mph. Makes me a laugh every time. You lot can do what you like.