Yes, get tiered up. Here's an idea...make a shirt that would appeal to family or friends and then buy 4 to give as gifts. You'll get to 10 sold and have some Christmas shopping done!
And it's all about Christmas...you really want as many shirts as possible up and running for the Christmas rush.
I'm about a year ahead of you on the curve...started in Sept 2016...and the 25 shirts I had live last Christmas convinced me that Merch is a goldmine.
Today doing 4k a month with Merch.