I certainly prefer to swing the faster weapons myself, they work well enough and in most cases you won't notice too much difference while using them. I also suggest you locker or get rid of the weapon you aren't using and carry as little as possible at any given moment. I may not always follow it but it is good advice. As far as stamina goes I am unsure of how you are training but I'd suggest you max out physical fitness until you reach your maximum health points then decide what to do from there, either slow down the fitness training till it reaches 1x or to keep it at 2x, there are often good reasons for either path depending on preferences and society choices. Training in fitness is your primary source of stamina, you get 1 stamina per 3 bonus, so while you get a lot very quickly it will soon diminish to a trickle.

The easy answer, which you should take with a grain of salt, is to move your skills to THW and use a claid until sonic weapon.