Well, I found that a part of the reason. When I changed the bots to testbot, it gets far better, usually ends the movement of a unit within 1~2min. and even on the very complicated situation(full of inferno fire areas nearby) some of them are needs more to run(more than 5min for limited situation, perhaps it was a bit complicated to resolve). Also it says it calculcates for how many units right now(it was reduced from 4, 3, 2, and 1 before finalize the movement) so it was more easier to check. It seems that making many bots and distribute the units to them was finally have some meaning, for it does not making much difference on princess.
In contrast, Princess(which is the default bot on AtB) usually takes five minutes or more only for one unit's movement. Although I have spammed inferno Arrow IV many times, I have seen more than 20 or 30mins to make the movement of only one unit even on the first turn of the battle(that doesn't have much dangerous area) recently. Even if my force only have around 12 units on the field and either forces are far from the range. Well, the map was 40x40 so it may a reason, though. I was really consider running them manually but at that time I was found that testbot is far faster.