I don't know Sakiko well enough to really voice my opinion on her, but I'll give it a shot.
I'm glad she gets the space within AKB48 to use her musical skills. The piano intro at the Yoyogi concert was really cool.

She looks so strong and almost menacing at times, but I like how she's still very feminine. During the danso bits on AKBingo she got tears in her eyes from digging it so much

She's almost like a 'gap moe' character, if that makes sense.