The Sunbow may well need more water like you thought.
Mine have doubled in size since I sent yours. They are outside in 90+ degrees and getting 2-5 inches of rain a day. It was a very wet June.
The Little Stars x Maiki should be growing faster. Possibly the new home has set it back some, if so it will catch up.
Here is my control plant. It is one year older. It was the size of yours in January 2007 and here is its growth since. It is in a four inch plastic pot inside the clay slip pot. Look at the growth rate in the last two months.
