Composite is fixed resolution (720x480@60i for NTSC, 720x576@50i for PAL).
You can’t output 480x234 over composite.
So your display will be resizing the composite signal down to the display size.
So forget about resolution, that is out of your control. You just a skin that fonts large enough to be readable.
Confluence isn’t bad for composite resolution (although your display’s additional resize down will make it worse).