I've thought this, but considered a few things. Troll racial is getting nerfed slightly, and with t17 set bonuses our CA won't be on a 3minute cooldown, unable to line up with Berserking. Even with Glyph of CA before t17 if we use it before combat on pre-pull it might be slightly off the 3min cd of Berserking. So, I've wondered is 15% haste for 10 seconds without cd's at some points better than 2% crit damage all the time the times we actually do crit?
Maybe it's me wanting to try something different since I've been a troll the past 4-5 years, but I may decide on Tauren unless it's blatantly obvious that's the wrong decision in the end.