I always felt that the bases advantages are just as much a disadvantage.
Examples.
TB can use explode traps on bridge. The other factions can trap TB bridge just as well, making hit-and-fades impossible and forcing the defenders into an "Alamo" defense.
TB can use guards to defend. Just as well, the other factions can use them to attack.
I've seen the portcullis ruin, easily, as many defenses as it has helped. As a longtime loyal TB'er, I can say I'd love to see that damned gate removed.
The choke points in Minax and SL (ridiculous as they are) can also be easily used to block reinforcements.
Minax base itself has a nice advantage with it's "Alamo" (never used that twice in a post before) in the mountains. Just as well, their mobility becomes limited. Ever try to run from a beetle or a greater dragon in that small of an area? Ouch.
5 things that might improve factions a fair bit:
NO MORE PORTCULLIS!
Eject players in an enemy stronghold upon "timing out". You can log out an entire army in TB base, or use a thief to run around for hours. As a dedicated thief, I truly believe TB base is a faction-thief's Valhalla. Log out a large group of people in a small area like Minax or SL base, and you can completely sandwich them against their own defenses. Bah! No more logging in bases!
Detect hidden (passive and active) need to only work on the same level of z-axis as the player using said skill. SL base is already "Mission Impossible" for us thieves, let alone someone somehow passively detecting you as you scale the many floors/levels of SL base.
Make it so traps may not be placed adjacently (any trap). This should just be a given.
For heaven's sake widen SL. I can live with the 2-tile chokes...but the 1-tile passes are ludicrous and need to be widened.
Edit: CoM base...yeah...the only thing that has going for it is everyone will be dead on the traps before their lagged client catches up with them. Damn, Mag is unplayable.
My liver hurts after all that typing....I think that's my liver....Hmmmm....now I want some liver and onions....