This is about external dating, in-sys relationships/dating are not as complex as this and also very common among systems, this does not make a system less valid nor makes it "cringe", an in-sys relationship is something that has been often associated with healing and self-love. I must add I am in a in-sys relationship with people that I love and trust very much. However, that is not today's topic.
Dating is already hard enough, you have to find the right person, you have to share interests in some things, you have to meet and know each other deeply, trust each other completely, getting into a romantic relationship is hard, even for a singlet. Now, there's even more thing to consider when you're a system.
If you're part of a system and want to date someone outside of that system, you have to contemplate various things such as: How much time are you able to spend with that person considering your front times and patterns? Are the rest of the system even going to like my partner? How much are they actually going to like them? Might other alters fall in live with them too? What gender is okay with the rest of the system to date? Who in the system are aromantic or asexual that might not like to get in the relationship? etc. It's such a tangled mess of boundaries and communication and trust, but I'm not saying that it is not possible.
Once you have found the person (or even another system) you are sure you want to date and you have talked it out enough with your own system, it can be such a good experience, but you have to get boundaries through, not only yours as a individual, you have to get the boundaries of your system, and of course the other person (singlet) must know about the system, is part of the trust that you have built on each other.
About those boundaries, it is important to acknowledge if your system have littles in it and how to manage with them, how some alters have different love languages, how to deal with those hard to reason alters, how to deal with the otherwise fragile alters, it's so much that you have to let know the other person and you have to trust that they will actually respect every single member, because that's one thing that's beautiful about dating, that you can have this person along side all of you that understands and helps you through your journey of being a system.