I am sure that with your pace one day you will end up doing a full circle around all retro consoles if that is your intention. While there are a lot of encyclopaedias about the popular ones - NES, SNES, N64, etc. there is a certain middle ground between retro and modern consoles that no one has covered - PSP, GBA, DS etc or there are some big failures as consoles that no one really wants to write about - CDi, 3DO etc. I am personally collecting systems only (currently reached 70+), however I always needed some sort of a list when selecting the best games on a console to play so that I can beat at least those and put the system back in the box and on the shelf. Even Wikipedia doesn’t have an entry for every game or pictures regarding each title, this is where your books come into play, since I can quickly have a usable reference about ratings and a summary for each title.
The only field I am truly missing is whether a game is exclusive for the platform or not or what it’s also available on, but I guess since we live in the age of constant remasters and remakes such section might never grow old well, requiring updates to stay accurate.