Ok bbq party questions:

A) Sauces
I usually make mine hot, sweet and sour. Think brown sugar vinegar hot pepper in a tomato base.

Trying new ideas, because keto. So one idea is still tomato based with vinegar and hot pepper, hot and sour but not sweet.

Another idea for the hot-pepper wusses is maybe maple syrup mustard? Garlic honey mustard is a thing, and this one can be sweet, but should look different, unconfusably. I have maple syrup but not honey.

Other ideas? I'd like to make several, like 4.

B) Ribs
I have 2 full racks, d'où 4 sauces desired. The ribs will be pre-par-cooked low slow oven. I am thinking one rack in dry rub and one in pineapple juice? Other ideas?