That would be a personal preference. Switching to carbons you can shed up to 100 grains in weight which would give you about 20 fps more or less (based on the average of 1 fps per every 5 grs). You would have to find out what speed you are getting with the alum vs carbon.
There are pros and cons with both types. Alum are heavier thus more energy. Carbons recover faster from oscilation and all else being equal, have better flight characteristics. But KE is not the only factor to consider. Without being accurate with the numbers a slower moving heavier arrow will normally give you more penetration than a lighter, faster moving arrow even though the KE is the same provided the resistance is the same.
Recommended Arrow Energy For Bow Hunting25 ft. lbs. Small Game
25-41 ft. lbs. Medium Game (Deer, Antelope)
42-65 ft. lbs. Large Game (Elk, Black Bear, Wild Boar)
65 ft. lbs. Toughest Game (Cape Buffalo, Grizzly)
KINETIC ENERGY FORMULA

KE=(mv²)/450240
m= weight of arrow in grains; v=velocity in fps