If you eat more, you get bigger. Ditto for the plant. More leaves= more photosynthesis=more food= more plant. Leave them alone, the genetics will sort them out.
Roll on, Bud :)
Check your ph levels, don't overfeed or overwater, keep temps 27-30c, light breeze for air circulation, don't fuss too much, relax, deep breath, see what tomorrow brings.
If they're not from feminised seeds, you need to sex them before choosing otherwise you could end up with males in ur mix. Other than that, what other criteria are there?