My first job was VB6 and I really enjoyed working on it. It was pretty late in it's life - .NET had just come out when I started. The existing program I was working on was pretty complex though. I spent a year rewriting the database layer (well, it wasn't a layer when I started but it was by the end) from an old cursor / file based system to use SQL server. That extended the lifetime of the product by quite a margin as it had been struggling with bigger customers.

It was really stretching the VB6 runtime by the time I left - plenty of direct win32 calls to do various things - foggy on the details now but VB6 was single threaded and some of that was around keeping the interface going while it did more intensive tasks, drawing some complex controls around scheduling etc. I recall it got a bit unstable in development.

Website for the software is still there too not sure if its still used, I left in 2007. https://www.redrabbit.uk.com/oli/oli_overview.htm I drew those little pinball people in inkscape.