Technically there is no rule for delaying in 5e (though I think there should be). But being able to walk through allies seems like it'd at least partially solve your problem and is allowed by 5e rules, so at the very least +1 to that.
Can't comment much on your 75% except to say make sure you have Weighted Dice turned On in settings. Without it (at least as of patch 3 or 4), Larian's rng system was statistically streak-y: if you rolled a low number, you were more likely to roll another low number next time. The Weighted Dice fixes this by doing the opposite: if you roll a low number, your next roll is more likely to be high (and maybe vice versa...I forget exactly).
