My two cents, i have tried about four different home style machines, a couple would sew ultralight leather, 1 mm or so thick but with great difficulty and a lot of tinkering your wife wouldn't like. I've went down that road wasted a bunch of time, leather and money and found out what others already knew.
I'm sure more knowledgeable will chime in but as far as any real leather work the answer is no. The leather machines costs thousands for a reason.