Hidden Maintenance is worth it because you can do all the capture beacon contracts.
In Blackwood you can do only the beacon repair contract.
As already mentioned. Hidden M is easier but takes more time than Blackwood. With a good team you can do Hidden M in less than 8 minutes. Another advantage in Hidden M is that you can get enough efficiency with all ship roles to complete efficiency contracts.
Another thing. You can fly every ship role in all stages as long as you know how to avoid dying and you can still make some contribution.
What ship role to use in what stage depends on the ships others use and in case of engineers if the engineers are good enough to keep everyone alive.
My opinion/suggestion about the stages:
You can bring whatever you want but it would be good that at least one person is doing engineer just in case someone is not paying attention. You can share assists between multiple engies with not doing all auras or planting a repair/recharge station.
You can also share assists between commands when having different resist auras active or using the Valkyrie system.
For those flying ships that don’t get any buff assists like Gunship or CovertOps you can take out the turrets (usually at the beginning) next to Beacon C. Each of the 6 turrets gives you 90 Efficiency. If you destroy the turret on the beacons by yourself you get 105 .
Each beacon capture gets you 100 efficiency but you need to be next (and capture a little bit) to it before it is capture.
Capturing only in the beginning doesn’t count.
You capture beacon in Order A - B - C . IF you are in a good team on not everyone needs all beacon captures you can maybe split up, but out of my experience that sometimes doesn’t make it faster.
In any case, if your are alone at the end of stage1 it is impossible to capture the last beacon because the bots constantly shooting at you and blocking/countering your capture. Of course that is no longer an issue with the latest patch which allows reviving ships.
The first stage is the easiest stage and where you usually get half of the efficiency of the whole PvE.
Here you need to have at least one good engineer, meaning at least green auras and stations and good survivability. If you are not sure if the other players engie is good enough (should notice that in the 1st stage how fast you heal) bring a 2nd engie.
This stage is about destroying the main weapons as fast as possible (2minutes). The longer it takes your team to kill them the less like it is to finish the stage. It would be beneficial to have a good guard in your team in case it takes a little bit longer.
You fly with your team to the right of the dreadnought where you have a blind spot so that the turrets from the top and bottom deck cannot shoot at you but you can shoot at the main weapons.
There are a couple tricks to still finish this stage when only you are left but that takes a while and it is faster (more credits) to just get killed and start a new PvE.
Avoid the top deck as there are dozens of turrets (thermal damage) which can kill fighters and frigates very fast, except you know what you are doing. Killing a turret by yourself is again 105 eff. The turrets not destroyed will be in the next stage but don’t affect you in completing the 3rd stage.
If you are in a good team you try to take them out on the top deck at least especially when someone wants to do fighter or inty in the 3rd stage.
left from the dreadnought you have blind spots where turrets and missile launchers cannot hit you but you can still hit the missile launchers. These spots are good for frigates.
Like in the stage before you need at least one engie. I guard would be good too but not really required, a 2nd engie instead works too. Watch out for the Launcher in the back (the last one) which deals around 10k damage per shot. It single shot/kills Intys and poor fitted fighters and frigates also don’t survive that many shots.
Focus on destroying the missile launchers. The missile launchers go to the target the is closest to them. Inties have blind spots where they can be right next to them but cannot shot at them. This is an advantage for everyone as everyone can safely shot at close range from the top deck dealing more damage.
Regarding resistances . I think as long as you have no negative resistance you are fine in all stages. All stages have all types of damages from bots.
Equip your ships to deal the most damage, for frigates that means heavy blaster, fighters singularity, Inty anything but Shrapnel.
fF you have good Engineers in stage 2 and 3 you can use LRF as gunboat (heavy blaster with curved reflector) to deal an insane amount of damage to the main weapons/missile launcher and finishing these stages faster .