When it comes to upgrading, you're never going to be 100% ready for it...there's always going to be something new that you're going to learn about flying after you upgrade.
Do you feel as though that you're mentally prepared to handle most situations that can arise during a flight? Do you feel like you can handle flying with an FO that knows more about the airplane that you do (assuming you upgrade into a plane you're not currently on)? Do you feel like you can handle being a fairly new Captain (less than 500 hrs time in type) and flying with someone fresh off of IOE that might do something really dumb? Have you seen most of the facets of the company in terms of the types of flying?
If you can answer yes to those types of questions, then I think you'll be ready to upgrade and it won't be something that you can handle.
I had a friend upgrade at Trans States with 1700hrs TT, he had started there with less than 500 hrs. I didn't think he was ready to upgrade, purely from the standpoint of that when he got off high min's (1800hrs), he could be flying with a fresh FO with 500hrs/little experience and he'd be responsible for everything at that point. That's a great deal of responsibility to place on someone that has less than 2000hrs TT.