This patch make Xfce use "gnome" as the default icon theme and enable font antialias.

Taken from ArchLinux.

diff -upr xfce4-settings-4.12.0.orig/xfsettingsd/xsettings.xml xfce4-settings-4.12.0/xfsettingsd/xsettings.xml
--- xfce4-settings-4.12.0.orig/xfsettingsd/xsettings.xml	2015-02-24 03:33:11.000000000 +0200
+++ xfce4-settings-4.12.0/xfsettingsd/xsettings.xml	2015-03-01 09:52:24.376869688 +0200
@@ -6,8 +6,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <channel name="xsettings" version="1.0">
   <property name="Net" type="empty">
     <property name="ThemeName" type="empty"/>
-    <property name="IconThemeName" type="empty"/>
+    <property name="IconThemeName" type="string" value="gnome"/>
     <property name="DoubleClickTime" type="int" value="400"/>
     <property name="DoubleClickDistance" type="int" value="5"/>
     <property name="DndDragThreshold" type="int" value="8"/>
@@ -19,9 +19,9 @@
   </property>
   <property name="Xft" type="empty">
     <property name="DPI" type="empty"/>
-    <property name="Antialias" type="int" value="-1"/>
+    <property name="Antialias" type="int" value="1"/>
     <property name="Hinting" type="int" value="-1"/>
-    <property name="HintStyle" type="string" value="hintnone"/>
+    <property name="HintStyle" type="string" value="hintfull"/>
     <property name="RGBA" type="string" value="none"/>
     <!-- <property name="Lcdfilter" type="string" value="none"/> -->
   </property>
kages/lirc.scm?id=54bee9ea2eee1bd93657f6817bf7cc7aed3b18a6'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/packages/lirc.scm'>
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<div class='path'>path: <a href='/guix/log/?id=54bee9ea2eee1bd93657f6817bf7cc7aed3b18a6'>root</a>/<a href='/guix/log/gnu?id=54bee9ea2eee1bd93657f6817bf7cc7aed3b18a6'>gnu</a>/<a href='/guix/log/gnu/packages?id=54bee9ea2eee1bd93657f6817bf7cc7aed3b18a6'>packages</a>/<a href='/guix/log/gnu/packages/lirc.scm?id=54bee9ea2eee1bd93657f6817bf7cc7aed3b18a6'>lirc.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/lirc.scm?id=54bee9ea2eee1bd93657f6817bf7cc7aed3b18a6&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-01-25 13:21:19 +0100'>2019-01-25</span></td><td><a href='/guix/commit/gnu/packages/lirc.scm?id=4c523c45353095d389f1093725069a6475c4f1b3'>gnu: python-lirc: Update to 1.2.1-2.c28708b.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2019-01-15 14:46:44 +0100'>2019-01-15</span></td><td><a href='/guix/commit/gnu/packages/lirc.scm?id=44d10b1f722856ab8e9b942804aa7ef33e2ef739'>gnu: Separate Python core packages from the rest.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-11-29 14:11:35 +0100'>2018-11-29</span></td><td><a href='/guix/commit/gnu/packages/lirc.scm?id=c324ad52b6066b4626312a4120b645c43989dd0a'>gnu: lirc: Build reproducibly.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-09-28 18:43:22 +0300'>2017-09-28</span></td><td><a href='/guix/commit/gnu/packages/lirc.scm?id=41342e89ff9a78e48d347c36d830bcfb17f62456'>gnu: lirc: Update to 0.10.1.</a><span class='msg-avail'>...</span></td><td>Alex Kost</td></tr>
<tr><td><span title='2017-06-26 16:35:56 +0200'>2017-06-26</span></td><td><a href='/guix/commit/gnu/packages/lirc.scm?id=794cced614fd5e0800b478b4a1735f861fa8a5e2'>gnu: lirc: Fix building on Ubuntu.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>