Each technique requires a level of finesse and has pros and cons. 

Microplane: 

+ produces very fine texture hash that looks great

+ approachable, from a tools and conditions aspect. The tool is $20 and every one has a freezer

+ preserves trichome head integrity to a high degree 

+ not highly time dependant

-difficult to scale 

-planing a consistent product is challenging 

- has unique processing requirements (sheet trays, and space to dry) 

-loss of yield from tools, trays

Sieve Drying 

+no risk of glove/finger contamination

+ideal technique for layering hash evenly on trays

+outstanding terpene preservation

+dry hash texture is appealing and very favorable to handling/ processing

-color loss, one to two shades 

-trichome head damage from sieve process

-loss of yield through sieve, tools, trays

-highly dependant on resin texture and characteristics. Requires care and attention to conditions and environment 

-non-flexible timing. Hash must  be sieved at the right time. 

Well that's a start. It's tough not to get into the air dry vs freeze dry nuance, but let's try to leave that to another post.