Something a little more tightened up might be nice, because who likes scanning for line endings, when you could have a byte count, and what's up with the colons

Something a little more tightened up might be nice, because who likes scanning for line endings, when you could have a byte count, and what's up with the colons, and while you're there, might as well have a single byte command, right? But preferably without having seven layers of byte counts, like TLS. But from my recollection of writing bad IRC client in the 90s (including in mIRC script after they added support for sockets in the scripting language in mIRC v5.3 released December 1997), the protocol isn't that hard to work with. Once you figured out you needed to send a : in front of your message text, I don't remember any other big gotchas. It's not XML, and I don't remember any quoting issues, but maybe there's some I forgot. CTCP maybe isn't ideal either. DCC probably doesn't work anymore, but it was a different time when being on the internet meant an expectation that you were a peer and could accept inbound connections.