In my opinion, The Witcher 3 rides off The Bloody Baron story for the majority of the game. It's the best story mission in the game. But it's also the first story mission in the game. Everything else after just feels like your standard fantasy stuff. And with that combat, it makes it somewhat of a chore to go through a lot of the missions.
With FFXV the combat greatly helps in getting through missions so far since it's so good. So even if the story points aren't as impressive as The Witcher 3, I feel like as an overall package, it might still be more enjoyable.
I think there are moments of greatness later in the game, but the BB and the interlocking sub plots surrounding that quest line are absolutely the game's highlight in terms of storytelling.
And I think I agree, I'm just finding this game so much more appealing to play than TW3. While the latter engrossed me often with its excellent story, it never came close to the utter joy of FFXV's traversal and combat.
One of the main things I look for in an RPG is combat that can be repeated for hours at a time and still be fun. I used to grind like crazy in older titles in the series while exploring the various upgrade/enhancement systems. FFXV has I've me that and I didn't realize how much I'd missed it. The last time I felt it was FFX (and to an extent FFXIV).
It helps the open in FFXV feels so rewarding to explore. Random encounters with powerful foes, hidden prices of exposition and character development, treasures and collectibles that have purpose, dungeons, etc...
It really is a joy to play.