Lol fuck that man I like the big pics, keep em comin
Everything looks fucking great so far man you seem to be doing the cheapo-budget grow just right. I hope those seeds do you right and you turn out with a bunch of females. As far as the plants looking different, you may be dealing with an unstable strain and you're seeing the different genetic phenotypes. I grew some Hawaiian Big Bud from seed and I swear half the plants were long and stringy and half were short and fat.
If I can make a suggestion, however, I'd say not to use clear cups next time. Really there are lots of better containers you can find around the house to grow in besides cups anyway. But if you're gonna use cups like that, I suggest you use at least the red party cup-type or at least put some tape or paint the ones you have. The cups being clear let light in and algae are able to grow in the soil and on the roots. I know its cool being able to watch the root development and all that, but its bad for the plants
With that said, just keep a close eye on em and give em love and I think you'll have some good weed to smoke my friend!
PS. To get an idea of how well they'll do in slightly larger/more efficient containers, heres an 14 day old seedling I grew in a six inch pot.