WHAT GIVES! Two minutes into this map, your defences are GONE, your core is being attacked by every mech ever and you can't do a danged thing to stop it.
Well... Maybe at first...

The trick here is to buy yourself breathing room until you can clear some of the mech-maker outposts yourself.
You have a lot of power going to no good use. Use that for some Arc and Lancer turrets at the two main 'danger' areas.
Re-enforce that wall! Take your pick of how, but again; spare power. Use the Mend Projectors and don't be afraid to use a Force Projector over your defences.
ANTI AIR. Seriously, as much as I like the Salvos, they can't keep up and some dedicated AA Scatter turrets with just raw lead will keep those Revenants from opening a back door for your enemy.
Well... That's a start on the base. If you want, now's a good time to set up some VERY QUICK builds. Nothing that will take too long because the next wave has already been sent and the one behind it is, nope, too late, that's been sent too! (I build myself a Glaive pad and a few Spirit and Spectre drones direct from the core)
Now, time to be a good leader and LEAD THAT FIGHT! Lead it along the outskirts and look for some small enemy outposts puking out mechs. Destroy them any way you like (As I said, Glaive... The other ships/mechs have their charm too. Your call)
Now you have dealt with the immediate threat, keep checking your wall to see if you have any breaches.
Still alive? Check your watch. Probably 5-past you usually died here, so let's get on with the next bit...
RAID THE ENEMY BASE!
This is where you will be sneaky, cheeky and downright unfair. Pick your favourite form and start doing some damage! The longer-range the better because the enemy repair drones are well-defended and will need to be taken out if you want to do this in any decent time. You CAN take out the majority of the enemy spawners, but with the swarm of repair-drones, if you don't take it out fast, it'll be back to full health before you respawn.

After crippling the enemy bot production, try to screw up some infrastructure.
After here, the victory is yours to take as you see fit. There's no real 'best way' because of the nature of diversity and not being a fascist.

TL:DR Use power to make wall better. AA defences. Destroy the drone outposts. Shoot the enemy base up the rear. Profit.