In the old version Active tasks where black and inactive where grey. This allowed a quick visual on where notes/ tasks delayed/ etc...
also colour is not used to identify tasks in any way in V2 which would be a huge advantage to get a visual on projects and tasks.
The second part about not wanting to add colour because the algorithm and associated coding would be too taxing for the modern smartphone is perplexing but my knowledge of programing stops at fortran and machine code.
I do wonder though why V2 is visually less interesting than what it replaces. (Really appreciate the enormous leap in functionality btw) I have not upgraded MLO on my phone and look at V2 on my tablet wondering what happened to blue folder icons, yellow note icons, green headers, blue radio button selectors, green text to say active action in edit, green text on opening screen ... really better to look at...
... also 1 touch expanding of folders... but swings and roundabouts I guess.