This is my first cube I consider a built cube. I had a previous cube I started on, but it lacked a theme and direction.
Choices -
Pauper - Budget was a concern, and I never wanted to get to the point where I was saying 'oh, [insert expensive card here] would go great! I have considered peasant/ artisan, whatever the uncommons allowed is called these days. The biggest upside to that plan would be improvements to blue as it has one of the most shallow counters pools.
+1/+1 Counters - I considered a few different options for the theme. Ravnica was the other main option, but I went with a mechanical theme instead.
Twobert - I don't get out of the house much, so I rarely would be able to have a pod. A twobert I can convice the Wife, or teach my son to play. Also limits the number of cards I need to collect.