Good strain indicators

Random thread out of boredom.

I just mentioned in my journal about one of the plants showing signs of being a good strain. But until the final product I can't be sure. Can be great grower but crap smoke.

But out of interest, let's say you are growing out a bunch of seeds (from different strains) to get a mother, you have everything dialed in, so all plants have equal opportunity.
What growing traits do you like? what traits do you consider make for a good strain? do you have any theories (crazy or not) about signs a plant is going to be good smoke before they are finished (any stage)?

doesn't stretch, gives a good yield, potent to the smoke, doesn't have too much variability between seeds.
i had a sativa recently taht didn't stretch...made a nice short bush. yeild was ok, high was good too. it's one i would recommend...you can even cut around the time the breeder suggests and get good stuff.