Little Retro Pants

I was browsing through some of my old craft books recently when I saw these awesome knit pants for kids that buttoned up the side of the pantleg. Sadly the pattern in the book wasn't for the pants, but the coat that went with them. I thought the pants were so cute that I tried to make a spin-off linen pant for my guy (given that my knitting skills probably aren't even adequate to knit pants, much less sans pattern).

What I did was take a pants pattern I had and cut it up the outer hip side. Then when I cut the front piece out, I added a couple of inches on each of the bottom pant legs so that I could form a tab when I sewed them up. I'm somewhat happy with them, although they are about 100 sizes too big for my guy. I'm tempted to sell this pair and make another, much smaller pair for Baby Pumpkin. I'm thinking these are about a 2T (19" waist, 16 1/2" length from waist to bottom). And what to wear on top...?