Yeah. In particular,
creatures that can fly should be exterminated as soon as they appear on map, regardless of disposition or intent. Fliers have increased pathfinding costs, ridiculously so I might add since their movement consists of useless flapping most of the time. I do not respect birds in Dwarf Fortress and neither should you.
Only god can help you if you have a large population of nearby Kea.
2. Does fortifying caves help in a long run?
3. Did anyone seal map entries in reasonable time without cheating?
The method for quickly walling multiple z-levels is as follows (for premium):
-1.
Collect or prepare a large number of the same block or log. Do not use raw stone. This is very important as stones are heavy af and take forever to drag into position, while blocks and most logs are lightweight.
0.
Have 10 or so dwarves with nothing else to do but construct the wall. This step is what makes this process fast - disable labors for as many dwarves as you can spare, since every free hand is needed for hauling, block construction, and building the various tiles.
1.
Construct up-down stairs next to the position of the planned wall, extending from the bottom to the top. Your dwarves will build this 'scaffolding' without the need for micromanagement, but you will need many logs or blocks to construct them in one designation.
2.
Construct the wall. Now that you have scaffolding next to all planned wall tiles, there is no need to worry about accidental cave-ins or collapsing tiles. Simply ensure your dwarves are guarded to avoid mass job suspension.
3.
Starting from the top, deconstruct the scaffolding one z-level at a time. Designating all the scaffolding at once will result in very annoying leftover stairs. Alternatively, you can just leave the scaffolding if you don't mind how it looks. This also allows for later repairs or modfications..
The new ability to designate multiple z-levels of construction is worth highlighting, for this process.
I would also suggest you install DFhack for 50.08, as it allows for automatic material selection during the construction process, which saves a lot of clicking.
Another tip - pick a single material to build from, and make a LOT of that material. having 200 or so stone blocks on hand at any given time is very very useful.