I have been playing Fire Emblem since Blazing Sword was first released in the US, and this game absolutely finds a place near the top of my list. The jury is out on whether this is my absolute favorite; only time will tell, and I haven't had it for nearly long enough yet.
"To die without leaving a corpse... That is the way of us Garo."
I'd expect the next one to top this off easily, what with the lacking plot and maps (rout rout rout rout rout). Regardless, I've clocked in over 100 hours on this already.
It's really a pity how the story drops after Gangrel, especially with how the timeskip was handled. Walhart's introduced as a big strong menace, but he is steamrolled within ~4 chapters in his own turf. He should have been an optional boss at some point like the Black Knight in the early chapter of FE9, just to make you crap your pants when you see him, then you'd have to pull an underhanded tactic to beat him in his last chapter.
Depends on how you play it, I think. Being able to grind makes any difficulty trivial, and the pairing and children system makes it easier as well since it makes some terribly broken characters. Class changing was simplified, which I like, but also makes for a system that is easy to abuse by switching classes to re-level for maxing stats. The TONS of FREE spot pass characters and maps is great, and the paid DLC is pretty good, though three of the maps you get give you unlimited exp, gold, and legendary weapons, which makes the game entirely too simple. But overall I love the game, with custom avatar and choosing who to pair up, the support dialog, all the free weapons and items you get from barracks, etc. It's fun and exciting. Though, that feeling is fading quickly unfortunately. Future DLC and challenges seem worth the wait, and running on Lunatic and Lunatic+ really tests your nerves, and keeps the game's longevity, so long as you avoid grinding.
All in all, while I enjoyed playing the old FE, especially the GBA ones, I find I enjoy Awakening more. I relied on save states for the GBA games quite often to get me out of having to replay whole levels when a unit dies. With Awakening I have to soft reset and rethink my strategy, but usually in the end I just end up dropping whatever unit keeps dying and tanking the level with my avatar and chrom and their spouses or children. Some characters are just plain glass cannons.