Special Buildings from Adventure

Can we enhance the drop rate percentages of special buildings by adding a new feature like a completed adventure counter with a guaranteed drop

My suggestion is to drop the special building in either condition:

(1) Random percentages (as it is today)
OR
(2) Guaranteed drop if you have done the adv a number of time equivalent to the percentage above

For example,

If a Dark Castle has a drop rate of 4% then the building is dropped by either
(1) getting lucky with the random percentage
OR
(2) after completing the adventure 96 times without getting the building, on the 97th time - you are guaranteed the building

Also, make the counter visible so you know how far you are from the next building and
make the counter reset to zero every time you get the building either way.

There will be different counters for each building type regardless of the various adventures they could be dropped from so a Witch Tower counter will the sum of Roaring Bull and Dark Brotherhood completed adventures.

These counters could be implemented like an achievement but with the reset to zero every time a building is claimed

This way, everyone is not frustrated in getting a building because they know that somewhere along the line, the effort will get a success. This will also encourage more people doing adventures since there is an end goal and not just a pure luck situation.