Is this character design alright?

jellophish

Ruko's Ruffians
Defender of Defoko
Hmm I would say more on his design but all we can see is his head.
From the head view his hair and everything look fine! You could spruce up his headphones a little, and add a little more design on them.

On the file being too big, you should resize it if you need it to fit. MS Paint, Paint Tool SAI, Photoshop, and many other art programs have this feature :D