Basically every aspect of what people like/dislike about a certain stick is subjective(length, flex, lie, curve, blade pattern, so on and so forth). What two people of the same height, weight, size, and skill level might drastically differ between the two.
The general rule of thumb with flex used to be to take your weight, and cut it in half, and start with the flex closest to it. Not sure if people even go by that anymore.
In all honesty, its best to start with one and work your way into trying a bunch if different flexes, blade patterns, etc. Guys are usually more than willing to let you get the puck feel with a stick they are using, so you can get the idea of different types of sticks.
Personally, if I were you, start at an 85, play with it, get used to it, then try a bunch of others, and compare your findings.
I'm 6'2", and over 200 lbs. Though I don't consider myself extremely strong, I find 100 flex sticks(for the most part, it varies between manufacturer) feel the best to me overall.