Any trilogy tips for a returning Engineer on insanity?

Haven't used Engineer on ME2, but I have beaten ME3 on Insanity with Engineer.

The name of the game is power recharge.

By limiting yourself to 2 weapons and choosing power recharge most every time, you'll be using your powers every 2-3 seconds. With Combat Drones and Sentry Turrents being your 4th and 5th squadmates, you can keep all the bad guys off of you, and you'll still have a quick enough recharge to throw out an Overload, Incinerate, or Cryoblast whenever an enemy does get too close.

My go to strategy so far after importing a save is max out Liara's Singularity. Then I spend every fight zapping shielded enemies with Overload, getting three at a time. They then float helplessly and I unload my assault rifle on them or send up an Incinerate. Overload is pretty crazy on everything that isn't armor too. Unprotected enemies collapse thanks to the neural shock upgrade.

Garrus is also invaluable. Not because of his God Mode, but because of his Armor Piercing Rounds, his extra Overload for me to use, and his Land Mine, which is basically an unlimited grenade that always hits and hurts armor.

Sabotage of course turns Cerberus turrets into a joke. Along with any environmental shields.

I also use the bonus power Dominate from the Leviathan DLC. Giving me a 6th squadmate to turn the enemy side into a clusterfuck. Especially if you want to count Tali's Combat Drone as a 7th squadmate and the hacked Cerberus turret as the 8th squadmate.