From my perscpective the financial aspect of retiring early was the easiest part of the decison. Numbers are straighforward. Spend estimates, ROR on equities over time and inflation numbers can be estimated from a conservative perspective. Sure, you can spend your waking hours focused on them but they are constant. They are easy to understand and quantify.
The harder part...perhaps walking away and leaving a few years worth of of m money on the table. But...that may always be the case. That tinge of greed and desire to acquire that is present in most of us.
It came down to two factors for us. The first was what were our plans for retirement. Did we have any, what did they consist of.
The second was how many healthy years do we have left to enjoy an independent life and do the things we want to do. You cannot buy healthy years. Nor can you accurately predict. So it was a function of the value of those estimated healthy retirement years.
These made the financial aspects even less important to us...especially the one more year or two scenerios.