Not a single person so far has mentioned any of these 3 back's games during the Fantasy Playoffs. I'll include weeks 14-16 since I have a 3 week playoff in one of my leagues.
week 14: vs. Denver
week 15: vs. Kansas City
week 16: @ Seattle
week 14: vs. Baltimore
week 15: @ San Diego
week 16: @ Oakland (Saturday game)
week 14: @ Arizona
week 15: vs. San Francisco (Thursday game)
week 16: vs. San Diego
personally I like Alexander's schedule the best. Even better is that means the Denver, Kansas City, and Oakland games (including NY Giants and Chicago) have already been played. They may need
to win those ARI and SF games which means a heavy dose of SA! On top of that week's 15 and 16 are home games...
As far as consistency goes there's no way to really gauge. Each team has had their RB go for 15+ TDs in each of the last 3 seasons.
I think LT probably has the least amount of risk involved since he's been doing it with a horrible cast for years now but his ceiling is limited. LJ has the most risk but probably the higher ceiling. That's why I like Alexander this year over anyone else.