Yes I am sure that Claire is a spoiled little princess and that she is doing well with a cat pal or without :) But if a second cat should move in it is always good to be at home for some time. As you said you can watch over the two cats but the new cat would get used to you sooner and better, too when you are at home 24 hours a day.
Haven't ruled it out, but I would want to wait till I have 2 or 3 weeks off to be around to supervise the "getting to know you" period. Until then Claire really does do well on her own as long as I lavish the attention on her.