I've had 2 coolant related issues...water pump and yes, the cap. Issues were unrelated, but frustrating none the less. In your case, I would suspect that only the cap was at issue and wouldn't worry much more, but keep an eye on temp. If you look around the forum, you will find that pumps (for some reason) are an issue...unfortunately I cannot give advice on how to check the health of your pump. Actually, forget I even mentioned the pump...I don't want to add to your concerns.
. If the tank looks good, I wouldn't think about changing. I suppose that one could argue that tank replacement could be considered a "proactive maintenance" item, but with that logic, everything would be.
