I'd say go where your motivation takes you. Let's say you are burning to do idea 1 - so do it! Then you may get burnt out for the weekend and not want to do idea 1, so start idea 2.

Mainly keep it very focused, don't over-engineer, use the customer-development framework and keep refining to the very simple core of the product.

I think these things take time so you will be glad that you flowed with your momentum. In a couple months I'm sure you will gain the experience to answer this question unequivocally.