These two have a serious flaw, and I feel that it could be fixed relatively easily.
I've noticed what might be an oversight - the correlation between age and lifetime. Currently, age is dependant on the lifetime of the star, never being older than the lifetime. However, here is a problem I've noticed: age is calculated from the formation of the star, while lifetime seems to be calculated only for the current evolutionary stage. This gives implausible results, such as two solar-mass orange giants being a measly 200 million years old, while the age should be in billions of years.
Also, a minor suggestion not related directly to the problem itself, but it is related to planetary ages:
It would be nice for planets and major moons to have ages just slightly smaller than their parent body, to represent the fact that they weren't all formed at the same time. For moonlets/inner asteroidal moons, the ages would be much shorter and randomized almost totally.
Interesting point. Generally, I also agree with the second recommendation, although it would be rather arbitrary as to what exactly "slightly" younger can mean. A number in the single digit-million years spectrum would be realistic, though.