I finished Half-Life series recently and what I learnt is if I played it again I would play it with MMod. Its game overhaul, but it tries to keep its origin. It refreshes graphics to suit modern systems in clever way. Some gameplay tweaks show up, but thats it.

If you have never played Half-Life series, but wish to play it one day, I really recommend these mods.

https://store.steampowered.com/app/1761270/HalfLife_MMod/

https://www.moddb.com/mods/hl2-ep2-enhased-mod