I think there is also a huge market space between deckbuilders and LCG/CCGs that remains untouched. This seems to tap into that by making a LCG format affordable and accessible. I'm developing a game that tries to step into this arena by making deckbuilding easier and require less investment of time and money. Good to see others are starting to fill out this zone too.
POD's greatest advantage though is the ability to test and innovate. The previously impossible speed of idea to table makes it easy to explore mechanics and the market. For instance, you have 5 games that you've created in the last year on Drive Thru Cards. While they certainly all have merit, some are probably doing better than others. You can look at those games now and try to reverse engineer why. What resonates with players the most? Is there something they don't like about the games that aren't selling as well?
When in an LCG model this becomes even more crucial. Some sets will only be favored by certain types of players that want to feature a particular strategy. Others will be considered an 'auto-buy' by the community. The 'meta' must carefully be watched for abuse of card combos and 'power creep'. POD allows you to respond quickly to the needs of a growing meta in a very agile way. It could be a quite brilliant innovative way to get into the Expandable Card Game model. I'd love to see what happens if you try it!