Light and heavy are two words that don't go well with spine. Spine is the ability to bend, not a weight, per se. I shoot aluminum arrows and I don't play with them to get EFOC, UEFOC, or other acronym of ambiguous nature.
I use bows in the 45 to 50 pound range, and my arrows are in the 470 to 520 grain range. With my 2016, I already have 10.6 grains per inch of shaft weight to work with. Personally, I'm shooting 28.5" arrow...303 grains tubing weight. Add 125 for point weight, about 25 for insert weight and about 20 grains for feathers and nock, and you end up with 473 grains on my 47 pound recurve.
Now, this setup, has taken a bunch of whitetails, squirrels, rabbits, pheasants, groundhogs, etc., and also shot an average of about 400 to 425 on the field course....many years ago 8^). I'm not the guy to talk to about carbon arrows and extreme fronts-of-center. I can tell you what has worked for me, and very admirably by the way, for the past five decades...60's through today. I can go as high as 145 to 150 grains up front without compromising spine and arrow flight.
I can tell you that 10 grains per pound of arrow weight won't hold you back in any competition, unless your form, or lack thereof, is preventing it. Lighter isn't always better...there is a happy medium that will work best for both hunting and competition.
There are guys here who use nothing but carbons and can expound on whatever they use, and the resultant configurations of point weights versus shaft weight, et al. I've not found any reason to change from what has worked for me personally.