Best settings for X-T100?

...you will get a variety of opinions, and no two will wholeheartedly agree.

Judging by your question, I'm inferring (I could be wrong) that you just got your X-T00, and perhaps are a novice when it comes to DSLR's or Mirrorless cameras in general?  And I didn't mean for that to sound sarcastic, which I wasn't trying to be.

Typically, if you are a beginner/novice, I'd suggest just putting your camera settings under Program, and then set Auto ISO.  I'd then also set your file quality to JPG Fine.  Under your various Fuji film simulation settings, you have a wealth of options.  The nice thing about it all is to try different settings, taking photos under each setting.  Write them down and then look at your photos in some type of software.  If you believe that more saturation is needed, change your Fuji film simulation setting - it's that simple.

The key here is that as time goes on, and if you've been keeping up with advancing your knowledge on photography and Fuji settings in general (i.e. reading these forums as much as possible, or other websites), you'll catch yourself experimenting even more, taking your camera off of P mode and delving into A, S, or M mode.  The sky is the limit to be sure.

Then there are those folks who shoot in JPG mode only, while others (like myself included) who shoot only in RAW mode because we want the extra headroom that these files allow for.

So good luck...