Well you are still supposed to distribute the license
(even if as seperate file as you mention).
But there's the other matter of restrictions,
granted the Artistic or MIT comes closest.
I guess another concern of mine is I wish to
express as little as possible because most
of what even the simplest licenses lay out
seems to be so much "common sense".
Even your licence has restrictions. For you to be able to impose your will - even if that will is "no-one will impose restrcitions on this software" - you have to claim the copyright. Hence, you need a copyright notice, and that notice needs to propogate with the software.
Don't underestimate the importance of correct licencing. We know the tilly story. We know stories of people taking "free" code and making proprietary software out of it. We also know of examples of people licensing their software with a licence they don't understand - see the popular UK firewall team who think that their software shouldn't be copyable, even though it is GPL'ed. Get the licence right, it saves a lot of trouble later...