Interesting thing about this thread is that most everyone is focusing on the low end of the damage, on the fact that 0-200% occasionally means deadly weapons don't kill.
To me it seems far more important what happens on the higher end. 150% max means you have a noticeably lower chance to get one-shotted instead of taking wounds, as a power/flying suit and even more so as a hovertank. Meaning game is more forgiving of poor scouting and positioning (= not a good thing, in my book). Let's do some math for fun (correct me please if I made any mistakes)
Take a rookie with 30 health using a power suit and getting a frontal hit (100 armor) from a heavy plasma (115 base):
Damage required to kill: 130 or more
With 0-200% rules, damage range is 231 long, from 0 to 230, and the killing damage range is 230-129 = 101 (damage values from 130 to 230 kill, damage values below that wound or do nothing).
101/231 = 43% chance.
With 50-150% rules, damage range is 116 long, from 57.5 to 172.5 (*), and the killing damage range is 172.5-129 = 43.5.
43.5/116 = 37.5% chance.
(*) I don't know which way the game rounds so I won't bother
Now 37.5% vs 43% chance to get oneshotted may not seem that much a difference, but we were looking at a rookie, and those are fragile in any case. Let's consider an experienced soldier - the kind we care about if they die or not - using a flying suit.
60 Health and 110 frontal armor.
Damage required to kill: 170 or more
With 0-200% rules, the killing damage range is 230-169 = 61.
61/231 = 26.4%
With 50-150% rules, the killing damage range is 172.5-169 = 3.5.
3.5/116 = 3%
Three percent.
Then you have the hovertank, which has 130 armor and 90 health... never mind one-shotting in this case, just consider max possible damage. 100 vs 42.
Now of course often you will be hit with entire series of shots, or not from the front, etc. Still... that's why I can't play 50-150% rules. Tried it, and it felt like easy mode.