It's better, but there's still quite a lot of unnecessary white pixels around the object/ on the sea.
No, the old one has better vibrancy with highlights.

Yes, they're much better in terms of visibility now.
Try increasing the brightness a little.
The others are okay, still low quality compared to average icons as mentioned, but for the sake of Warcraft II feels, they'll get a yes from me.
More opinions are welcomed, what do you guys say?
@The Panda @PeeKay