Noticed a lot of posts about editors and arrays lately.
I think you should probably figure out what functionality you have to have first.
Like a strip, or single tiles.
A strip would be fine for an external editor, but not really feasible for importing into construct.
That is to say unless you use frames, but you have to remember that each frame adds to the total ram each particular sprite takes up.
50 tiles at 4 frames each... you get the picture.
Now its been shown that you can use a strip via tiled background, but then again setting up the events for that would be a bit contrived for less experienced users.
So to me it looks like it should be tiles, but how do you want the editor to act.
Do you want to click, or do you want to paint?
Do you want a few basic tiles, or many tiles for corners etc.?
There's actually a lot to consider, especially when you take into account you may want something somebody else doesn't.
So what are the absolute basics everybody can agree upon?