Plus it's the only platformer to feature the PC Engine's full resolution mode: 525 x 248 pixels (widescreen). I might be a pixel of two out.
Where?  Most of Hero Tonma runs in 342 x 240 mode, unless I missed some hidden screens.  Anyway, 248 lines would not show up on any display device.  The visible maximum that I measured with the PCE hardware was 565 x 242.
Besides, you're forgetting Shadow of the Beast, a 
platformer with several 512-wide screens.