For Quake 2 I'd suggest Q2XP, along with model and weapon mods, then just tweak the settings the way you like. Played through Q2, Ground Zero, Zaero, and The Reckoning.
The only problem I remember was the screen flashing and having a problem seeing underwater but it's easy to fix.
Here's some screenshots including one to compare to Beserker.
https://imgbox.com/g/0BaQ6GLOkP
Here's a little readme I made while setting it up.
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Quake 2 XP
https://www.moddb.com/mods/quake-2-xp
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To turn off the screen flashing when being hurt
or picking up items, and from constantly being in
a "flash" state while underwater. Set (cl_blend "0")
either through the console or in xpconfig.cfg, or with
autoexec.cfg. Such a change likely needs to be done
for every game/mod.
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Quake 2 HD Monster Skins
https://www.moddb.com/mods/quake-2-monster-skins
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This is included, to remove it remove the following..
Folder
\baseq2\models\monsters\ctank
File
\baseq2\xFragHDSkinsx.pkx
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Quake 2 Weapons Remodel
https://www.moddb.com/mods/quake2-remodel
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Quake 2 Weapons Remodel content has since been
included in Q2XP with some replacements. So no
longer needs to be added, unless possible due
to updates etc.
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PS, this text box is almost impossible to use due to how hard it is to see the text...
https://images2.imgbox.com/39/46/JofpU2or_o.jpg