The classic theme is great... but it wasn't classic enough! I stumbled across the original assets for the original theme FS had in 2006 a while back, and I knew I had to recreate it.

This theme replaces the header, footer, and returns the XP bar to it's old look.

You can enable this theme in Character > Preferences > Theme.
 

Theme Code: (you MUST have classic theme enabled first for it to work)

.topbanner-normal
 {
    background: url('https://i.ibb.co/x76G9ZP/topmid-head.png') bottom left;
    height: 146px;
}

#xpbar {
    bottom: 36px;
}

#statbar-xp-progress
{
	position: absolute;
	height: 9px;
	width: 100%;
	background-image: url('https://cdn2.fallensword.com/ui/misc/progress_red.png');
}

div.buffListBuff 
{
    width: 25px;
    height: 25px;
    background: url('https://i.ibb.co/HrMTKWP/sheet.png');
    -webkit-box-shadow: 0 0 2px #000;
    -moz-box-shadow: 0 0 2px #000;
    -o-box-shadow: 0 0 2px #000;
    box-shadow: 0 0 2px #000;
    cursor: pointer;
}

#pF 
{
    background: url('https://i.ibb.co/5MVTB4d/bottom-banner.jpg') top center no-repeat;
    height: 96px;
    width: 1000px;
    padding-bottom: 5px;
}

To replace the skill icons, you need to have Tampermonkey installed. (the same extension used for FS Helper)

Download "ClassicSkillReplacer.user.zip" from this post, extract the file, drag and drop it into a new tab, install it, and finally enable it on FS.

Enjoy!