Both of you made some good arguments there. Let me give my point of view on both of them.
Sure but... an admin on your server should be someone you trust, not just some random dude you met yesterday or so. I wouldn't give admin to someone who's asking for it (obviously...). And a final note, if you don't need an admin in your server, don't give it to someone just cause you feel like you need one.
You're right. When I host, I don't often need an admin, and when I do, I give it to someone I trust. However, as you may see, I am not speaking for myself. There are others who are new/ignorants and don't follow this rule, or times where common mistakes are made (like, leaving your server without any kind of supervision, or giving admin to someone who seems to be trustable, but are not). But still, the abilities of a host or his mistakes shouldn't be my concern.
Of course, but this is about the admin's abilities. Wether the host is a moron and gives the power to another moron, then it's entirely his problem and shouldn't really be discussed here.
That's true as well. Some admins are not fit for their role, and can make a mess of a server. However, shouldn't the host be able to see whether a person is trustable or not? And shouldn't the host himself take measures if he decides to go AFK for a while? Even if the host isn't able to do these things, it shouldn't be one of my concern, and neither yours (unless you want to help him improve, of course). But still, common mistakes are made, and it's better to be safe than sorry.
In the end, my idea about setting privileges or restrictions for admins is debatable. However, you should consider bringing admin ban back. If you trust someone, you should be able to give him FULL control of your server, right?