MLS
 

the advantage of MLS is that it allows a curved approach or an approach at an angle towards a runway, however how would this be displayed?

i know that MLS would use a conventional ILS display however take for an example:

the aircraft is approaching at 270 for r/wy 30. as long as the aircraft is on that 30 degrees offset, the display will show that the aircraft is in line with the localizer. how would the pilot know therefore when to turn to 300 to align with the runway?

I haven't studied MLS in any detail, mainly because it's been all but killed off by GPS and, specifically, Precision GPS approaches, however I'd imagine that the localiser needle indication would keep moving to the right (in your example). The course which is thus followed by the aircraft is a curve.