A person who is a polymath knows a great deal about a wide range of topics. Is there a word for a person who is interested in a wide range of topics but doesn't know a great deal about them?
Jack of all trades?
In adjective form, I might say multifarious if your interests have found outward expression. As a noun phrase, a Renaissance dilettante?
Thanks Heimhenge and Glenn:
I think Jack of All trades suggests a competence in all of the trades: that is different than being interested in everything. Renaissance dilettante has a pejorative feel to it. But like multifarious if combined with interests. That's the way I'm going to describe myself until someone calls me on it. I am a person with multifarious interests or on second thought maybe we invent a new noun,"multifarion" I like that batter.
To expand on my previous comment, that phrase is often expanded to "jack of all trades, master of none." So it's almost implied, imho, that what is being accorded is merely "competence" aot "mastery."
And Garry, I do like your suggestion of "multifarion." Maybe it'll catch on.