i recommend you work with either Win' 296 or H-110, using Win's small rifle primer. that's right, use the small rifle primer in the .357 if you aren't doing it now. use a decent crimp on the cartridge with all of your brass trimmed one time to a consistent length so the crimp will be consistent. your 16.5 gr's of Lil' Gun is maybe not enough to give consistent ignition. the max' load is 18 on the Hodgdon website with the 158 gr' XTP. BUT, i've never tried that powder, being very happy with Win-296 and bulk powder WC-820.
you may want to put a Hogue monogrip on that revolver. just make sure you buy the right one. it will help with consistent positioning of your hand on the grip frame which is very important. it will help with recoil if that is a problem to you.
the Ruger SA in .357 is probably the best-buy in a .357 on today's market. it is bank-vault strong, and has a reputation for reliability. you should be able to make it 'sing' with proper hunting loads.
one last recommendation: go with either a 180 grain Remington JHP, or with the 180 grain XTP' for hunting. it'll penetrate better than the 158 gr' bullet on whitetails and black bear.
ss'