Any reason?
Personally MPC ui is far far better than most of the players. Only the essentials and you can add anything if you want. But not suitable for people who wants a smart looking ui.
http://www.codecguide.com/
here you can find new updates. But I'm not sure they are the original developers.
too many reasons honestly.
first. MPC is a dead player, k-lite isn't an update to MPC it's a pack of other ffdshow filters developed by others developers/teams.
k-lite and other codec packs are complete mess. most of them have abandoned or old filters that no one should use.
if you really want to add k-lite codec you can do that in pot as well but you don't need to install codec packs in modern days. pot & mpc all have good tools built in to the player. But if you are also a maniac like me, install only the filters you need like LAVfilters, madVR etc. and move to the new version of the filter as soon as developer releases without waiting for k-lite.
MPC provides descent configs relative to many other players except pot. pot's configuration allows far better configurations and UI is very descriptive and clear to do those configuration easily.
as you said looks most of a personnel preference, to you MPC UI is far better than pot but to me it's like saying windows xp interface is better than windows 10.