I can't recall who suggested this earlier in the thread, but I really like the idea of having a way to convert in-game gil to crysta in order to purchase things from the market.

The cash shop is obviously here to stay, and the prices just seem to be getting more and more ridiculous. I think it would appease a lot of the people who are adamantly against the cash shop as there would still be an "in-game" method (of sorts) to purchase the items. Plenty of other MMOs do this. I would imagine the exchange rate would be quite high (knowing SE), but it would be nice to have the option.