I like the 50 gauge over the 43 that comes on the 193 and 170 saws. I really prefer chisel tooth over semi chisel and, to my knowledge and what my dealer told me, they don’t make chisel tooth in 43. I do not think you will like putting a 50 gauge on your 193. I think you will find that’s too much chain for too little saw.
I do more removals than trimmings, even though I love trimming. Either way the 201 is 110% justifiable. Even on paper, the 201 is nearly 2x the power.
I bought a 193 and ended up with a 201 after I ran one for a half a day contract climbing. I pitched the 193 in the garage and then sold it. Hated the primer bulb, hated the plastic dogs, hated the small chain, hated the choke and then half choke. It’s very lazy in power and rip compared to my 201tc-m, the throttle response is fantastic on the 201. 201 pulls the 16” bar dogged in and buried in oaks, the 193 wouldn’t pull the 14” bar buried in soft wood. Both are 100% stock. Don’t get me wrong, the 193 will put food on the table and pay the bills, but if you ever get the chance to run a 201, expect to be dropping $$ at your local dealer. I carry my silky and my 201 into every tree, my 193 sits at home as a back up or very occasionally rides out for poplar or other very small soft wood trims