a new plugin for my server

hi. im looking for a plugin thats grants staff new commands in the chat. let me do a few examples
/help
- when you type /help a message automaticly chats into public chat with a message asking if anyone needs help
-because it would be very boring if all staff had the same message there would be a command that is
/help set (message) example= /help set does anyone need help? just ask!!! ^-^
/welcome
-on the server that i play on, you get welcomed when you join for the first time. so to make it easier for staff there would be a /welcome and would make a message
-this would be boring if all staff had the same. there for there would be /welcome set (msg)
/caps
there is a maximum capital letter limit in our server 4 per word 6 per sentence the same rules above apply

some more are /flood and /behave

i think this would be a great plugin. if it exists could you please tell me the name of it
thanks is advance matt

 

when ever somebody does anything wrong on the server they get told of and given a warn. flood is when some one randomly posts stuping things that flood up your chat box. example arfarjibqrgiwufbqir or lollllllllllll the limit of flood is 7 on our server. /behave would be used when someone says something that is not appropriate, our server is pg.
another would be /spam when you keep posting something less than a second apart example /tpa john. and spam him with that. another would be /doublepost and /doublepost set (msg)
this would make staffs life MUCH easier.can you tell me if there is a plugin like this?