I was the same way. IMO, philosophy is WAY underrated. If the takeaway from intro to philosophy courses is ancient Greeks had some strange ideas about atoms and such, that is missing the point. Below is for anyone that has never touched philosophy at all.
Ethics is NOT what the corporate ethics things say about following the rules. Ethics in this context would raise the question of whether always following company rules is the right thing to do? Is right and wrong objective or subjective? Is something right in some contexts but wrong in others? Which system of thought should you be using (consequentialism, virtue, deontological)? I was just following orders when I murdered those people! By our laws it was legal, therefore right! It is a great way to persuade people and make decisions.
Epistemology is absolutely key to critical thinking. How do you determine what you know vs what you merely believe? Can you trust that error message is accurate? Can you trust your memory? Personal experience? It is a great way to build a world class bullshit detector.
Metaphysics gets you to think about things at a more foundational level. Think about a stop sign. Is it a red octogon with stop in white letters? Not everywhere. It could be a cop or crossing guard with their hand out. It could be a red light. It could be a red sign that isn’t an octogon at all. It is a great way to learn to challenge your assumptions about the nature of the world and things.
So you want to advance to a higher level and have a broad interests?
You failed some MS cert exam?
You have a review coming up?
Broad interests. Don’t miss the forest for the trees. Learn core concepts and things that are useful in many contexts rather than specifics. This is where a lot of newbies go wrong. E.g. don’t learn about AD, learn LDAP and AD, OpenLDAP, DS389, will all come much easier. In most roles some basic programming with Python will come in handy. Once you learn to write code in one language, learning others comes a lot faster. Some worthwhile things to have a foundational grasp of: PKI and how it is used by SSH and TLS, a high level understanding of common network protocols. Peruse IETF RFCs for that. E.g. if you know how say DNS works, you can manage it using any DNS server software. Ditto http and web servers. You will need to learn configuration management SW and monitoring SW. I prefer salt stack and zabbix. There are many good choices.
Seriously learn PKI and TLS. I can recommend some good sources. TLS is used by pretty much everything to secure connections. Backup server to agent, browser to web server, AV to server, you name it.
Open Source is your friend, learn a bit about big projects. E.g. say you get good with backups and want to work for your favorite product vendor. That fancy backup appliance or cloud service is probably running Linux or FreeBSD on the metal and using something like Tomcat for the WebUI.
Learn a bit about licensing models. You will have to deal with it no matter what path you choose.
I wouldn’t try to impress your supervisor. Chances are, they’ll see through it. They may or may not care about their employees. Assume they don’t. Don’t assume the worst either. You can almost always trust interests. Their job in an MSP environment is to make sure contractual requirements are met and clients are happy. Focus on where your interests are aligned. Happy clients mean less headaches for you and your boss. I would let them lead the conversation, but focus on that aspect. If a lot of clients use X thing, mention that to your boss that you want to learn more about X thing as it will help you close tickets faster.