Okay I don't really play tournament games but I'll try and give you advice based on what I have found effective and not...
Firstly, I think Rangers are a no go for tournament games, they are easy to squash with the amount of ignore cover that is out there and will more often than not give your opponent first blood. And even if they don't they will probably barely scratch anything.
I used to use them back in fifth and they were great. They became less reliable in sixth and now they are even worse. I would recommend against them.
Also the fire dragons seem out of place considering you fill their role with the wraithguard and the war walkers... Which also will remove the need of the falcon because I've heard that they aren't very competitive, but I've never used one personally...
You don't seem to have much that can actually hit infantry... And you also have nothing that wont struggle in close combat. Maybe try and slip a wraithknight in there to draw some fire away from the smaller targets and give him/her scatter lasers to help deal with infantry. Or even give him/her brightlances and then give the war walkers scatter lasers.
Other than that it seems fairly solid, maybe a few more jetbikes wouldn't go amiss but other than that it looks pretty stable. I like dark reapers so go ahead with them, guided by the seer for even more of an impact.
No comment on the hawks as I haven't used them...
But yeah, It doesn't seem like a bad list