Lightroom :: Add Equal Exposure Boost Across Whole Shoot

It seems that even with a calibrated screen and across multiple print labs and colour profiles, my prints will always come out about a third stop darker than what looked good on the screen. I attribute this to the screen emitting light vs. the page only reflecting it. My question: is there an efficient way to give an equal exposure boost across an entire shoot? I don't want to sync a specific exposure setting. I want to make virtual copies for print and then add maybe 0.3 exposure to all files, on top of their current setting.
 
The only way I can think do to it now is to export 16-bit tiffs which will reset the exposure to 0.00 for those files, and then sync them all at +0.3 exposure. This is really inefficient for time and hard drive space. Even a preset will only set a specific overall exposure setting. I want a preset that adds exposure to the existing number.