If you want all those NewIcons to look better, you need to increase your Workbench screenmode to High Res Interlaced with 16 colours. If the colours look off, you'll need to download FullPalette from Aminet and lock your Workbench colours.
You'd really be better off getting yourself a Kickstart 3.1 ROM. You can get cheap ROM switchers and other things here -
http://www.amigamaniac.com
