CMS --
In terms of objective data, you can find data regarding ammunition performance in ballistics tables. That is not subjective - it's quantifiable.
Same thing with manufacturers specs on handguns - length, width, height, trigger pull, # of rounds, etc.
In terms of comparisons, looking at this data will identify which handgun is a bit thicker, or carries more rounds...
But ultimately there is no objective comparison regarding which CCW firearm will best fit your needs. That's because whether the gun is right for you or not is subjective. Some guns will 'feel better' in your hand than others, you will often inherently shoot better with one than another. This isn't quantifiable, and hence isn't objective data. You can only discover the best CCW firearm for your needs by trying different options - one will fit your hand and your style better than the rest.
(It gets even more complex - one thing I've discovered is that the optimal firearm that I carried in my 20s and 30s is not the optimal carry gun in my 50s - what is "right" for you may change in accordance with different phases or periods in your life. Alternately you may have 2 or 4 optimal choices and rotate them based on time of year or your activities, etc.)
One idea has frequently been proven true for many CCW carriers, however:
The small, handy gun that you can carry quickly and conveniently is the one you'll most often have with you. The larger, heavier, more tactically effective handgun will more often get left at home. It's something to keep in mind when you are pondering your choices.
Best,
Doc