To me a nemonic is supposed to provide an easy way to help you remember something.  It shouldn't be hard to remember or hard to remember how to use.  The second nemonic, I feel, is quite complicated, has much information buried in it, is hard to learn how it all goes together, and takes a significant amount of memory to remember how to use all its various parts.  Given that, is it really a nemonic?

A second thing I want to do is give for consideration the nemonic I learned way back when we used paper trig tables.  Sorry, I do not know a reference for it.  And I can not edit it in, because I don't know the markup here on Wiki.

It is:  OH,  AH,  Oh-Ah,  Ah-Oh,  HA,  HO  (Say it moderately fast).
Sine, cosine, tangent, cotangent, secant, cosecant are:  O/H,  A/H,  Oh/Ah,  Ah/Oh,  H/A,  H/O.

Unlike the soa-cah-toa nemonic it gives all six common functions.  But I like to teach only the 1st three, OH, AH, Oh-Ah (simple enough), or even only the first two, OH AH  and have them (students) memorize only Sin, Cos, and Tan   then have them learn and understand that tan= sin/cos and the last three are inverses of the 1st three.

It might sound a bit like a tongue twister at first, but it only took a my high school trig class about 15 minutes to learn it and a good part of that time was laughter  and it is silly enough to be memorable. I still use it after 45+ years and some of my today's students have picked it up too as the one they prefer (over soh cah toa).