I'll be the one to throw a curve ball here. I just turned 66, have 45 years at my current employer, and am hesitant to retire because my career is beyond description in a good way (I DO accept the benefits of retirement/the ills of married to career). I was in your shoes my entire career - just an Associate degree with workplace free college classes benefit (I took many).
I chose to continue my education my entire career, but not pursue a higher degree. My personal achievement was more important than my "height on the ladder" achievement. I am beyond content and have very few regrets, but I admit to being an oddball. You don't mention family (kids), so I assume classes will not interfere with that priority. It "sounds" like you have good income between you and your wife, and my "oddballness" includes not making wealth accumulation a key life motivator.
You have some hard personal questions to answer:
- Are you doing this to please yourself or to please others (follow the crowd)? You sound excited to pursue classes, but at the same time hint that you feel guilty if you don't take advantage of this opportunity of a lifetime. Your OP sounds like they intend to move you up the ladder regardless of advanced degree. So, if you choose classes, it should be because YOU desire to, not just to please the "system" IMO.
- Do you want to manage a "team of Administrators"? Good lord, that is like trying to herd cats. Probably should take some baby sitting classes. I chose to remain at a certain level of management and purposely stayed under the radar regarding the upper level politics, back stabbing, ego games, and cut throat activities. That suits me just fine. Others enjoy that challenge. Many are miserable at that level.
To sum up, dig deep into what you want out of life. If more education and/or ladder climbing gives you pleasure, then by all means pursue it. If your passions direct you elsewhere, embrace them and don't look back. Follow YOUR heart, not other's. Most here won't understand my idealistic outlook, but it works for me.
LOL, college students hated me - gray hair guy only taking one class - always messing up the grading scale with 90+ scores.