I started out long ago(1966) with 1/72. It had the largest variety and was inexpensive and took up less shelf space. When I started earning money at about the age of ten, I probably built at least one a week. I built mostly WWII, but have always had a soft spot for biplanes, so I built all the WWI kits available too. Of course there were a few box scale Revell ships in there. Oh, and the 1/28 Camel, SPAD, and Dr.1. In high school I built 1/35 and 1/32 scale armored vehicles but aircraft were still 1/72. About 15 years ago I started building 1/48. I could spend more time, it was easier to rig, and I wasn't building at the same rate. Now I was building WWI and between war with an occasional foray into WWII and god forbid, a jet or 2. With the coming of Roden and WNW( and age), I build in 1/32. The kits are more accurate and I get to learn new skills which keeps each successive build interesting. Plus I have great inspiration from the owner of this site and all of it's members.
Sean