Long before I found this site - probably back about 1998 - I built my own Microsoft Access database (this was basically after using Excel for several years and outgrowing it). Since I only collect a single player, I think that the database I created does a pretty good job of allowing me to keep track. Each record has details about the card I have as well as a scan, front and back, so it is like having my collection right there with me. The beauty of it is I can carry it around with me on my Surface tablet and do not need Internet connectivity to know exactly what I have and need. This can be very helpful if I am at a shop or show and keeps me from accidentally buying doubles. Also, the power of query language and report formatting allow me to create reports using very specific criteria. Within the same database I also maintain a contact list where I can keep track of names, addresses and details about other collectors or merchants I have dealt with.
Works well for me, but I still really like this site too. I don't believe there is a one size fits all type of product and you sort of need to pick and choose the best bits and pieces from various sources.