Well, if you have predominantly infantry, it might be good to draw in the enemy without advancing too much, at least with the Guardians. You'll want them to stay near the Support Batteries to give them Preferred Enemy per their formation (and also to protect it from Drop Pods and stuff).
Actually, Jetbikes and Falcons/Wave Serpents with units mounted in them might make a nice hammer to drive the enemy to the Guardian anvil. Sounds like it could work in theory at least...
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Nope. The only army I've ever let go of was an Eldar army my dad had that I didn't paint. Even if I'm not playing games with figures I've worked on, I like to keep them around as personal art.
Besides, I always hold out hope things will get better. Because I'm insane and for some reason haven't learned my lesson from life yet.
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Well, have fun with all these amazing new powergaming codices... but having had to wait three editions for my last codex update and getting one right after 7th dropped, I'm not looking forward to waiting for 10th edition and seeing every other army get all kinds of amazing stuff while my army was the example that GW had calmed down and decided to make an army without anything seriously strong or broken. Clearly that example was wrong, and the Space Wolves already started making it seem like a fluke, and now we're right up to "Screw you in the bum with a rusty fork, Ork players! Go play a REAL army like Space Marines or Eldar!"