Collectible Card Game Headquarters

Hello, I've noticed there are several cards missing in older and not so older sets (even m13 is incomplete).
Is there a roadmap to complete one set at time or are cards added in a totally random way such as a developer wants a card so he adds that card alone?

Would be nice to have a sets roadmap to complete all the sets, this way it will be easier also to track down the missing cards and incomplete sets.
So let's say for next month the goal is to complete FUT for example, then another set and so on.
I'll see if I will be able to help too, have to study a bit before though.

Eg. FRF 100% 185/185 completed
KTK 100% 269/269 completed
..
..
..
M13 90% 224/249 [missing this, this and that] (totally invented numbers here)

What do you think?

Status is already tracked here:

http://ct-magefree.rhcloud.com/stats

Order is:
Tournament relevant
Newer sets
Developer preferences

At least in theory

Isn't this way a little bit too err..."sparse"?
Wouldn't it be nicer to complete one set at time? (always keeping in mind to finish standard sets earlier when they come out of course)
I know standard is complete, which is really nice, but let's say I want to play with a particular set, I know it will be more likely incomplete.
I mean the whole Time Spiral block (Future Sight, Time Spiral, Time Spiral timeshifted, and Planar Chaos) is mainly complete at just 50% for example and it's not an "ancient" set, it's still used in modern quite heavily.

P.S. My bad M13 is complete, for some reason when I was looking for M13 Cathedral of War it wasn't showing up, maybe even resetting the filters something went wrong.

I think it's more helpful to implement cards played in tournaments by the winning/better decks than to implement all the special cards of a set that are maybe played in limited block tournaments but nowhere else.

At least there is some ambition to complete the sets one by one going back from standard.
But its' not always plain fun to implement cards. And so I guess every developer tries to find his own litte motivations to implement a card.

Btw: Which cards of M13 are missing?

M13 is complete, as I said in my last post it was some kind of mistake, probably the filter didn't reset itself even if I set it right.
I was looking for Cathedral of War and it didn't show up. Restarting XMage did it, so now it is showing.