The Witcher 3 GOTY vs DOOM...HELP ME!

Well, value wise, of course Witcher 3 because you can potentially get hundreds of hours exploring and questing in the open world setting, whereas DOOM, unless you're going deep into the MP scene, you'll most probably get around 20 hours or so of AMAZING single player campaign. You can't exactly compared between the two to begin with since they're two different genre. It's up to you whether you're up for some RPG or an FPS game.

Just know that you can't go wrong with either of the title.

Witcher 3...why do you even ask

Nobrainer - Witcher 3

Neither. I see you don't have them in your library, so get the Half Life Complete Bundle for much less and play some of the best games ever made.

caz i'd rather get lost while being deeply immersed in a plot line for 200+ hours, than squander the same amount of money on a 10h, as some have put it , leisure, easy-to-get-into, arena-after-arena-clearing shooter; even tho I, admittedly, adore the new Doom. so, the 'obvious' recommendation from yours truly.