I searched around for a suggestion like this, but didn't find any.

Basically, I think we should have a building that acts like the sanctuary, but for sqauds. My reasoning is this: When you're using an individual pet, there are three ways to replenish its energy--give it an energy drink, send it to the sanctuary, or wait for it to replenish on its own. When you're using a sqaud, however, you have only two ways to replenish energy--give them a squad energy pack, or wait. The new building would have the same limits as the sanctuary--you could only use it once a day and only for one squad, for one extra move. It could either be an entirely new building, or an upgrade to the existing sanctuary (as in, once you upgrade you could use it on one pet per day and on one squad per day). I don't think it would unbalance the game any more than the current sanctuary building, perhaps less--the current sanctuary gives 10 extra fights in the arena, for instance, but this would only give one extra battle on the battlefield. Thoughts?

It will be too overpowered and unbalanced. It's quite possible to defend the portal from 4 attacks to get a reward if you have decent squad. But 8 attacks will kick you out of there almost for sure before getting anything, no matter how good your squad is. The more tries you have, the better the chance of success. Current tactics system was designed for 4 attacks per cycle. Adding such building will require rebalancing and changing the logic of all of the tactics, including the battlefield map itself.