Years ago I wore some old mountaineering boots that had caved in ankles on a long hike and probably permanently damaged my ankles. I now cannot have anything touch my ankle or it gets almost like squeak heel. I hiked in regular tennis shoes with superfeet insoles for a year before I could even go to light low-cut hikers. If the sole is thin, you can always add a sturdy insole like Super Feet. Low cut "light hikers" are between a trail running shoe and boot. That might work for you if trail runners do not. Fit is the most important thing. If I find a fit, I am not too fussy if it weighs a few ounces more or less.

I am in the "start light" camp. At least if the trail runners do not work out, you have a good pair of athletic shoes for home. Then work up as needed. Try insoles. The big PITA for shoes is that you really do not know if they fit until you have done a several day hike of many miles, carrying a pack. By that time, you cannot return them. And each shoe can have individual differences. I have tried on several pair of the same brand, same size and they all felt different. Manufacturing of the shoe is not so exact that each pair are exactly the same.

As for pants - I cannot do shorts- I just do too much off-trail, but I do not like the "swish-swish" of long pants and I like lots of knee room. So I use knee high gaiters. Solves both problems. Plus keeps out all the debris, ticks, and is tough material when bashing through brambles.