Nuke the Covies, Glass the Heretics, Cleanse the Infection.
I personally am kind of torn on the topic of Forerunner design. On one hand the Bungie era forerunner artstyle is i c o n i c and sort of portrays the mystery and lack of life that the race embues. But the 343 designs kind bring the technology and complexities of the forerunners to light in a more realistic sense.
Like how in the books the Forerunners were portrayed as having lots of micro slipspace bubbles, dyson spheres inside of impossibly small points on a planet entirely made of sentinels, rooms that had strange ways of traversing them to actually progress without being trapped in a temporal reference frame. Lots of time, gravity and robotics.
But in more recent books became weird things like walls that absorbed you in weird ways to enter an unknown room, strangely specific gene seeds, and giant knife robots that EMP planets.
I prefer the old style for its iconic feel and simplicity but I also kind of see sense in the new styles, fitting moreso with the descriptions of the rates and the technological advancement of them as a race.