I'd vote for keeping the same fabric weight. My jerseys are perfect for anything but the hottest days.
I reckon a lighter weight summer jersey might be good but then would there be an issue with pockets ripping at stitching etc?
It's the weave/materials that produce the strength in the fabric not just the weight, so along with appropriate reinforcing a lighter fabric can work well.
It's the weave/materials that produce the strength in the fabric not just the weight, so along with appropriate reinforcing a lighter fabric can work well.