Some reasons for each option ...
Electric trim eliminates the big stiff cable from the build. In general, this is a one time issue. However, it does make removal of the elevator more challenging if you paint after phase one rather than paint before assembly.
With electric trim, you may want to insure easy access in the empenage for future maintenance.
With the manual trim knob on the left, just above and forward of the throttle, it is easy to reach without even looking.
Person opinion here - I found electric trim to be hard to judge but with manual trim, I quickly got the feel for very minor adjustments (eg turning 1/12th is often the amount if the the plane has a small climb/descend in hands off). With manual elevator and aileron trim, I found it much easier to get the plane in perfect trim.
Person opinion here - my plane is KISS for as many things as possible. carb, mags, fixed prop, manual trims, etc.
As is often said on this forum, "build the plane you want, not the plane others want you to build" - and - "build for your mission".