I'd take all the elements and scan them at 4K resolution and the effects at 8K. Hell, why not just the entire film and composite effects in 4K? Get rid of the garbage mattes, optically clean everything so there's grain which is true to the film stock used, scan the audio in a lossless format and other things. Save the 70mm magnetic track, 35mm stereo optical and such.

I'd do a Robert Harris type deal where I wouldn't remove film grain and disable all DNR and EE functions. Then I'd have a polyester 35mm print for DI archiving.

I wouldn't fuck around with anything. Just leave the movies as they are, just straight archiving and no bullshit. Got it? Good.

To Hell with 1080p films/videos. Film has FAR higher resolution compared to 2K.