How many queens have you killed so far w/ your no smoke/no veil criteria?Based on what I've seen and experienced. It's 100% genetic/pheromone influenced trait. I keep mine in the front yard. I can't allow anything other than gentle.
Size of the hive only makes a difference if they are mean to begin with. three frames of bees with the same queen mother will act just like 30 frames of bees with the same queen being the mother. Sometimes even with workers that are not her offspring. If I have to use smoke and a veil. I kill the queen. If I have to use smoke. I'll kill them this fall and combine with the nicer ones.
No tellin how long this selection process will take. I've got about 30ish queens mated out here this year and only three of them can be worked without smoke. I have one stacked three mediums high and one four. The four high one is well packed with bees. Not an issue. I can tear the whole hive down and spend as much time as I want in there. I shook about two pounds of bees out of it to help out other hives newly mated the other day. Cracked the box open 24 hours later. Still nice.
Test the bees at the entrance first. Wave your hand slightly in front. If they ignore you. Crack the lid. If a few run out and bump your hand or bounce off of you then you may want a veil. Or reaching for the frames if you notice them come out and bounce on you hands you might want gloves unless you can tolerate getting stung. The ones of mine that hit my hands when reaching for frames. The use of smoke usually stops that behavior enough to work them without protection of any kind. If not I kill the queen and shake them out forcing them to beg into a nicer hive.