Theorycraft based on my solo plays.
_Basement Morgue (done with fairly good success)
Plant one super patient player (non zerk) near the trader area watching the sink side and right door(spawn blocks the right door).
Zerker + Support on left door (one not near the stairs) - Zerker kills trash support helps if overwhelmed. Bored ranged from above can help with Medium picks if they go into LoS.
Commando located at the corner where pillar is looking down the hall that leads to the stairs to the fireplace (literally just up the small steps from where Zerker+Support should be).
2 Medics or 1 medic + 1 support/commando healing and providing backup as necessary.
The patient player and 2 others should keep an eye out on drains for crawler/clot/stalker popins.
90% if not all of the spawn should funnel right in from the door that Zerker+Support is watching due to the fact that Line of sight is preventing spawns and they are the closest to spawns without actually preventing spawning in.
If team feels overwhelmed, make a break for the patient players exit (right door) while 1 or 2 members play catch up slowly so nothing teleports.
From here, the demon statue fountain can be ok if the number left is manageable. Otherwise Garden holdout overlooking the sea or the outdoor balcony "U". Just remember to not have everyone running at once or else you will deal with siren/bloat combos and wipe.
_The outside "U" Balcony area as everyone knows.
_Spawn area/Chandelier(theoretical untested, considering each man gets their own lane very difficult unless you have competent team)
Put two Commandos side by side watching each door.
One medic in front of demon statue blocking spawn and watching the rightside staircase side.
Support, Commando and Zerker/Medic go up left side staircase and into the room where you can jump off into the library. For this group if a heal is required (without a siren in view) medic throws nade.
When a bail is called team moves toward either the "U" balcony, via the exit near windows or towards the pool room -> fountain depending on what the statue Medic sees.
Those are a couple of my theorycrafts, as stated I've had the basement done with fairly good success (not a full clear but all things considered not bad), the outside balcony works pretty well all depending on how quickly team can clear scrakes (or as long as you have a team that clears trash as one is circling and isn't full of a bunch a people that stares at the scrake as the team is getting overrun).
The major problem you'll have in pubs is that people get bored and move around and don't realize that just standing in a certain position is crucial to the teams success. If they knew that, literally any place will work as long as you manipulate the spawns.
