Sorry, I missed this reply on my first scroll-though, I guess.
I'll say this much: on a fundamental level, the two things you mention here -- the two lanes and the prophecy mechanic -- are a huge part of what makes TES:L such a good game. If those don't grab you, for whatever reason, then the game is probably not going to hold up to repeated plays.
I also like the how the attributes (colors, in other words) can be combined to make a variety of interesting decks. Each combination usually has at least two viable builds. Mage (blue/yellow), for instance, has a token build and a control build that are so vastly different that it's hard to believe they come from the same card set.
There's a lot else that's grabbed me, personally, but I'll stop before this gets too long. I'll sum it up with the inevitable Hearthstone comparison: there's not a single aspect of actual gameplay -- not one -- where TES:L isn't superior to HS. Name a category, and it's the better game.
(That could be a pretty low bar, of course, depending on your view of HS)
Also, for those who like expanions, there's a gigantic one coming out. It was due last week, but was pushed to April 5: