In my opinion, auto-trim significantly reduces pilot workload during critical phases of flight and is therefore a safety enhancement.
Not always.
I have written extensively on the subject of Auto Trim - one article can be found here:
http://www.rbogash.com/Safety/autopilots.html
If Dynon offered Auto Trim, I would likely incorporate it on my airplane. I think a major benefit would be elimination of these constant Trim commands while in cruise.
In other phases of flight - I'm not so sure. I don't consider it to be "workload" to know what your airplane is doing, and telling you, which it is doing when you need to trim - especially during the descent, approach, and landing phases. I think it's critical for the pilot to be in the man/machine loop, and trimming is one of the most important mechanisms.
Submerging the trim feedback is a mechanism for removing the pilot from the feedback loop.
Also, as described in my article, establishing conservative limits to the Autopilot's Trim Authority, would be a critical requirement to prevent the gross mis-trims I write about.
Bob Bogash
RV-12
N737G