I was bored so I decided I would make my own plugin.
I made it for Beta 1.7.2, but it works all the way to 1.7.4 and even higher!
I cant test 1.12 because my PC isn't strong enough :(
Leave comments if it works for you!
Options:

It's pretty basic to set up, you just have the second delay at the top, and every other line is your message!

here is the usage and the commands as followed.
Commands are:
/announcer reload
this reloads the Data file with the messages
/announcer next
this shows the next message
/announcer lines
this shows all the messages with their line number,
only to you
/announcer add <Message>
this adds your message to the end of the list and Data file
/announcer remline <Line number>
removes the message on the specific line number
announcer supports using color codes via &'s