Those MSJA 505s seem to have been designed on the following principles:
1. take a coach.
2. the driver needs to see out, so cut some windows in the end.
3. need headlights, cables etc, so bolt those on wherever convenient.
4. job done.
In other words only trying to make them functional, not even trying to make them look good. Pretty much the same I'd say for the 455s (the earlier design), and in fact most SR EMUs prior to the CIG/VEPs, where they went over to the "slightly-rounded" front ends.
Oh dear, I'm straying dangerously into "it's just a box on wheels" territory...
Edit: 309s and Transpennine 124 DMUs (and Intercity 123s) - the rounded windows did add a certain style, but I think they got replaced with flat panes because the curved glass was either too expensive to replace or was more prone to damage (or both?). Either way, function trumped aesthetics.