I'm a big fan of having my cake and eating it too... So for me, I do both signed and numbered limited editions and open unsigned fine art prints of the same work. You can view my site to see how I present these options.
Bottom line, if you can buy a signed limited edition of a Chagall and also buy an open edition archival print of the same image - why shouldn't you as an artist be able to offer the same range of offerings?
Some will argue that having both open and limited editions of the same piece is counter-intuitive. The distinction between the two is the signature and perhaps locking in on just one size/format for your LE.
It's all up to you. There are NO rules. In my view at least :)
J