It's cool you got to do these kind of things years ago. I like IRC as well, however slack has gone mainstream. Therefore these kind of bots should be adapted and implemented for everyone to enjoy!
Do you happen to have the code available for the bots you did? I could look at it for inspiration on other slack bots.
IRC scripting (with mIRC) was the first real programming I did, back in 2002. I can vividly remember, that I didn't have a clue about arrays or functions. I simply skipped over them because they seemed obscure to me. Variables I got rather fast.
I wrote so many chat bots. Also one like this. !seen bots were rather popular back in the days.
A Card-game bot, that showed you your cards via direct messages and the "played" in the channel.
I was so proud of my news-bot that used sockets to connect to channel related websites and posted news every hour or so.