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Your photos look nice on my overly bright monitor.
I find my star shots look flat and dark, more so than other types of photos, if not using the printer profiles, but you are. So here are a few thoughts.
1. Is your monitor calibrated properly, particularly for brightness?
2. You would edit a proof of your photo in LR using the printer profile, but still export it as sRGB profile.
3. I imagine your laptop monitor is susceptible to drastic changes in image appearance as you change your viewing angle. This could trump any monitor calibration, particularly for colors. You may want to consider a cheap ips external monitor.