I am no famous modder, neither my releases are, but there is something, I would like to recommend:
Firstly, don't be afraid of any ideas. If it's something you want in morrowind, you can make it happen more or less.
Secondly, don't start with huge project with an aim to amaze moddign society and veteran modders.
Thirdly, Do it as you want. People might recommend you stuff, but you should allways make your mods the way you like them. If you like the mod, you won't be the only one, trust me.
Dialogues are really easy to learn, I swear. Follow the link Pluto gave and you shall be fine. Quests are also easy to make.
I encourage you and wish you best of luck and welcome to modding society!
Cheers, have a beer! :foodndrink: