VVIS on a complex map properly done should only take 15 minutes max, maybe more if your map is super open.
Using a i5 4660 (if stating compile times this is a very important thing to note as this can identify diffirences in compile times a lot) it took me about 10 minutes of vvis on normal in giza, and that is considering a that a section is rotated and offgrid which can influence the compile time by a lot.
The number of stuff i func_detailed would be between 5 to 10%.
My map is 75% func_detailed. Some players even say that it is poorly optimised. But without it compiling would take more than 1 hour.
The only time you would have to func_detail something is when the compile time is exceeding an acceptable limit. You might have a small map, but if vvis takes 20 minutes on that, it might still be acceptable. Sure, it can be optimized by checking for high density areas (lots of blue lines when looking at the visleafs in hammer). But it might not need fixing. A 5 minute longer compile time can add 20% extra fps by just having that few extra visleafs that cut visibility around corners. You can manualy solve this to speed it up, but if its acceptable already, just dont bother unless its in/close to RC state.
Stuff you normaly should func detail (many hints are based on your example):
- Thin poles (essentialy anything that simply isnt thick enough to block any vision)
- Sections sticking out of a wall that arent the wall itself (window borders, supports).
- Arches (and make sure there is a solid wall behind the sides)
- Any brushwork in front/behind a window you can look through
- Grates
Stuff you should not func_detail:
- Regular walls
- Bridges
- Floors
- Ceilings
Anything that is essentialy blocking off a room is worthy for vvis. Keep these things there
Things you should use hints for:
- Sloped bridges (put a hint box around it so it can only create 2 triangle leafs in the slope - one above, 1 under).
- Any odd angled stuff (like a rounded pillar) could use a hint brush arround it to contain the triangle leafs to just that box
Things you need to add brushwork to:
- Displacements (you often want a nodraw brush under/behind the displacement to act as a wall for vvis since displacements act like func_details)
- Sections behind the playing ground can often be suitable for a skybox brush (which goes all the way to the skybox on top) directly behind it. Its not a good idea to keep the skybox a huge box.