Make it 2x wider. From experience, even if doubled in size, it's cramped.That, and real-life highways are huge.
That bridge doesn't look very good from the side. Bridges are never that thin, and they often have I-beams and possible support columns.
it looks too small to be practical for kart racingalso try not to have people read things while they're driving. just put up arrows
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I can see what you're saying now. Should there be a larger spawn area then have it funnel into the currently built area?