The opposed-corner indices should also be vertical rather than horizontal - with the card rotated 90 degrees. In other words, retain the orientation Paul used but place the pip under the value rather than next to it. It permits making a tighter squeeze when viewing the indices in that corner.
Doing what you mentioned forces the pip to take up more space if spreading the cards from a lefty direction, you'd have to move the cards father apart to see both parts if the pip. I tried your suggestion but at first glance I felt that ended up looking more "wrong" because it will visually intrude into space that should remain as white space. It looks quite misaligned when viewed as an entire card, so the 90 degree side-by-side was the most visually appealing and usable after lots of experimentation. It's also more interesting, as standard 4 corner pips have been done many a time. 
I suggested the tweak to the design based on right-hand poker players (as well as lefties accustomed to right-handed separation of cards in hand) wanting to make a peek at the table of their hole cards. By turning the cards 90 degrees and giving them a right-handed spread, you're peeking at the small indices - I suggested that using a "vertical" index in this rotated position would permit the player to make only the tiniest separation to make these indices visible. The smaller the spread, the less likely flashing will occur.
With this design, one could spread the cards vertically in the scenario I described, but that's a move most players wouldn't be accustomed to. Additionally, spreading right-handedly means the player has to push the cards wider apart, defeating the purpose.
If your design intent is to make the cards more convenient for left-handed spreading, well, it probably works fine. But it does appear that we're approaching the same issue from rather different perspectives. Left-handed players wouldn't be as common as only about 1 in 10 people are left-handed, and most lefties have become accustomed to the right-handed spreading of cards. I'm a lefty, and when I use Kevin Reylek's Bicycle Lefty Decks I actually find them a bit more difficult for table games like solitaire because of how accustomed I am to using right-handed cards.
