1) Whether through accounts, cookies, and a desktop app downloading the dats themselves, allow people a way to save their selections for the dats.
Thinking of this when it comes to updating a system dat but has countless options to go through to get how they are trying for. This would allow them to just go back into it and unless you guys changed something on that particular system and cleared it, it would allow them to just hit download as all their previous options were already selected.
2) When it comes to selected the regions, instead of having every possible combination of regions to choose from, just have it where you select the individual regions you are looking for and it will automatically select every combination that includes that region.
Good example of this, many systems have upwards of 15 different check boxes for USA. They range from "USA" to "Japan,USA" to "Japan, USA, Brazil", to "Europe, USA" and so on and so on.
With this change, just selecting "USA" on the list would select every version that included it. Would also make it where that list gets a good deal shorter and easier to read through as it defaults into looking like a giant run-on-sentence with how it is displayed.