I just had a hatch of a few chicks... visually inspecting them it was quite noticable that a few had what looked like bigger comb areas already and /or a bigger comb all together... does that mean anything? Or is vent sexing the only real way?
Nope, at this age a slightly larger comb area doesn't matter. A larger, reddening comb around 4-6 weeks old often means a cockerel, however. Vent sexing is the only real way to sex chicks at this age, unless they are a sex-linked breed.