The text size should not be an issue because the 3DS has a 2 4 inch screens which is plenty large to read a card of have a large hand. Also on the portability issue, which IMO will be on of the biggest attraction to the game, more people in the target audience will have a DS rather than a laptop.
Really? The DS isn't going to have a problem representing your side of the field (I would think the top screen shows the opponents) when you have lets say 3 things on the bench, a claydol, a curse gar, a mr.mime, spiritomb, dusknoir DP, and then a 7 card hand consisting of things like supporters, trainers, and pokemon? I think there'll be a problem somewhere.
Sabett, before we go any further, let's each define what we believe the goal(s) of a PTCG video game would be. I have no problems putting mine down and in order...
(1) Showcase the PTCG to those that only collect the cards and don't know a game exists around them.
(2) Showcase the PTCG to those that know the franchise but don't know cards exist.
(3) Showcase the PTCG to those that might possibly play competitively in the future.
(4) Allow for friends to play Any Time Any Place.
In order to fulfill each of these goals, the following limitations have to be placed on the game...
(1) It cannot cost an arm and a leg to get and play.
(2) It must be portable.
(3) It must contain internet connectivity.
(4) It must be updateable.
(5) It cannot be frustrating to play or collect ingame.
Your proposed MTGO clone fails on three of those five restrictions. It's incredibly expensive to play. It's not portable for most users. It is frustrating to collect ingame, and it can be frustrating to play.
My proposition is basically to make the original PTCG games for the GBC, but make it so that the above restrictions can actually happen. For this to work, it would have to be on an exclusively portable and internet-ready machine. Since nothing PCI does can ever be put on a non-Nintendo system, it would have to be placed on the DS or 3DS. The original method of card collecting can be somewhat frustrating, but it's also not money consuming like your proposition would be. The updates can be pay-for DLC, but Nintendo already has a system set up for paid DLC. And, being priced at the same point as a main Pokemon game, it wouldn't be outside the budget of a typical Pokemon player or collector. And, for the competitive or semi-competitive players, you can have an online battling system that's similar to the one currently used in the DPPtHGSS games.
What you seem to be proposing is a game or system that would appeal only to the competitive or semi-competitive player. Seeing as the majority of those that know about PTCG are casual or non-players, you'd need to market to those as well. This will (hopefully) pull more players into the competitive or semi-competitive scene, thus growing the game much more than simply attracting the competitive crowd.
You're forgetting a big one:
(6) Profit
And don't say Profit isn't an issue to a PTCG Video game, if it won't sell, they're not even going to make it. Not saying a DS PTCG wouldn't sell, just pointing out that profit is an issue. This is true for many reasons, enlarge their own company, and creating expansions.
You're wrong about it being expensive, first of all pokemon isn't expensive to play irl, second of all I just changed the suggestion to $1 packs and a $5 monthly fee, which is hardly expensive. What you suggest, through a DS, if it's going to entice more people to play, it means it's going to make people have to buy a DS, which is going to cost more than using this program.
Why do you keep on bringing up this portable issue? Laptops are portable, and yes not everyone has a laptop, but at the same turn, not everyone has a DS, and if they dont have a laptop, then they probably have a home computer.
I don't understand what's going to be so frustrating about playing and collecting cards on a program that doesn't exist. Kind of harsh judgment for someone who hasn't even played on the example I've given, magic online. FYI, magic online creates a fine way of collecting cards, allowing people to trade and sell cards online and be able to search for anything they want at any given time. And comparing playing the game on a DS to the computer is as I've said before highly in the computer's favor. There's way too much text for a DS to appropriately show everything on the playing field, where the computer works with such a thing just fine, as seen by magic online. So not that you can actually say it's frustrating or not, if you actually understood the possibilities of what could be done, the easier assumption to make is that it would be simple, not frustrating.
Once again, Magic online appeals to countless casual magic players, and even creates online unique casual formats to play on. So no, an online system does not only appeal to competitive players, it appeals to the casual field as well.