How much xp do you get for a win? How much XP do you lose for a loss?
Do you get more xp for beating stronger players? Do you lose less xp when losing to stronger players? Do you lose more xp when losing to weaker players?
That's the most important stuff.
If some guy plays 18 games a day as a premade against pugs and gets a high ranking off of it, then the ladder is still broken.
If some guy plays 20 games a day. wins 10 and losses ten, yet still climbs, the ladder isn't working.
if some guy plays 4 games a day, against the top 20 DG players consistently, and wins more times than he loses. that man should be around the top of the ladder.
Otherwise ladder reflects free time - and doesn't reflect skill. Which would render the ladder useless because you could just check players game timer instead of win / loss record and it would show you the same information.