I know what you mean - they're the decks that tend to not stand out as much because of the seeming simplicity of the pattern. Often they form a sort of optical illusion when you spread them, making it hard to tell where one card ends and another begins. It's one of the reasons why they're a favorite of card sharps and sleight-of-hand artists - it makes certain stunts of pasteboard legerdemain a little easier to get away with!
One that stands out right away is one that I consulted on for the designers - Pagan by Uusi. It was initially released in brown and ivory backs, then last year a special printing was made with a blue back as a partner deck to their Pagan Otherworlds tarot deck. I specifically counseled them to size the pattern to match the size of the Bee Diamond Back pattern to better produce that same illusory effect.
Another is a long-standing classic - Steamboats 999 by USPC. They're not in print now but they're not too hard to find the most recent reprints if you know where to look. It's a rather attractive pattern, in my opinion.
There's another interesting feature about borderless backs that have a simple, repeating pattern like you described. They have to be very precisely cut - if not, the resulting pattern can actually be read as a one-way design.