As far as the original question with out going to far off track. Aluminum heads are definitely better. Lighter and usually flow better with probably a little more compression. As far as everything else I couldn’t say. One thing I do know is that the cam your running isn’t fully utilizing
Maybe an xe284h would be a better cam, would have to cut the guides a beleive if it went in the stock j heads. But I would also probably need to go with 3.73 or 3.9 gears out back if I jump the cam up much