they r looking the way they should be so far. Not to sure about the 2 liter bottle idea. If u r going to transplant them sometime after the 2 liter bottle transplant, you might end up with a very long root system which could make it kinda difficult to transplant without alot of roots breaking off by weight alone. I would go with something shorter and wider. When you start feeding your plants, you want the plant to take up the nutrients as close to the stalk as possible = faster intake=faster growth. The further down the roots go, the further the fertalizer has to travel to get to the root, the soil is also "filtering" your fert solution. so if space is an issue and you dont want pots with big circumfrances, cut the bottle down to half. Hope this helps