Hmm .. actually, it looks ok on my screen, and the environment is quite dark, so, I want to preserve the mood. However, I also realized sometimes when I print out the picture, it is too dark. So, I actually have 2 profiles on my screens, one for normal viewing, one for printing. For those I am going to print, I will change my screen to another profile and do some minor adjustment like increasing the exposure or brightness, or changing the WB. I think this is the reason why you think it is underexposed. Actually, is there a better way to handle this? Because if I tuned my pictures with the printing profile, then when I look at it on other screens, like when I send the pics to my friends, the WB is too cool.
looks underexposed on my screen as well, so it may be that your "normal" profile is just way too bright. if you would like to keep the normal bright, then you can run some scripts or preset outputs to brighten an image by a certain amount prior to printing. you still i would still swtich to your print profile to verify it looks good.. but after a few successful runs you may be able to just run the script without verifying.
The last pic just seems a bit 3d-ish to me. It was with the 55-250 of all lenses.











