So I have been playing in a Lucky 13's campaign at a local gaming store this summer and it is really giving me a contrasted view to how I have traditionally played apoc games.
Even though I believe the games have been a little smaller in total size than the Georgia Tech Megabattles I have ran in the past, they play out very differently and I think it boils down to a few simple factors.
1- Emphasis on vehicles/infantry. I think the GT games have been geared much more to vast infantry combat rather than armour v armour. This is a very interesting way to play out Apoc in my opinion. Rather than being concerned with a superheavy duel or matching tanks co v tank co, you are playing more like a normal game on a grander scale. I recommend you try it sometime.
2- Balance. My club always strives to balance superheavies and points. We have done a very good job of this so far, with nothing dominating the game (other than a Super Monolith last time, bleh). But at Lucky 13's, people have shown up with Super Heavy flyers, which if you don't plan to fight specifically, they are nigh unstoppable. Titans are another thing that throw off the balance in a very similar matter. I suggest that unless you have a balance on each side of these things, then you restrict them. Baneblades and their variants aren't overpowered as long as oneside does not faild excess amounts against a side with none. But then again last game I destroyed a Shadowsword with 1 lascannon shot, so it can be done.
3. Scenarios. I think when players put their minds to it, they can come up with better scenarios than GW ever puts out. Asymmetcial, attacker/defender, crosslinked tables, amphibious assault, etc. etc. Give it a try.
Here is an example of a wacky scenario we have though of (but not tried) at my club.
You set up 3 sets of tables. Put what ever terrain you want on them. Then place "elevators". These elevators can carry infantry and walkers down to the next level, which should be set up like an indoor hangar/warehouse. Once again on that level there are elevators that go down to a bunker level. This table is accessible only by infantry and is laid out with corridors and rooms. Each table has 2 objectives (or more if you want, but make each table have as many as the next). You could even make certain things in certain levels effect the others, like a defence laser control room in the bottom floor grant control of a laser on the surface, or a building on the surface have secret tunnels to the hangar, or the hangar have a valkyrie to go up to the surface and a way to collapse a tunnel in the bunker.
Well there is just my general rant for now.