Well, i threw together a spreadsheet of my own, which does pretty much everything that you have planned for version 1.7 of yours (you said that 1.7 would likely never be completed, so i did it myself

) So far, my spreadsheet seems accurate (is it just me, or is the newest version's summoner HP really low?), but let me know if anything seems off. all of the included class data is directly from the master guide, so the class info should be up to date (if the stats there are the current version's stats).
the topmost part has a gender and a zodiac dropdown, the gender will automatically fill the base raw data in for all stats (so choosing male max will use the maximum value for all of the stats), and the zodiac option is to calculate the HP/MP as a zodiac would have. And along the side, the dropdowns there are for the class at X level (the level is listed beside the dropdown), so you can pretty much choose a different class every level if you wanted.
edit: okay, all classes are now added, directly from the master guide. i will have to download the most recent patch and look at the data from the game, to make sure everything is accurate.
edit2: all values are now in sych with the 1.3030 patch, directly from the iso itself. there were many inconsistencies with the master guide, but they are now all fixed (and written down if anybody wants to know the data that is outdated in that guide)
EDIT3: HURR DURR, i forgot to reupload once i fixed the mistakes a while back...
New Spreadsheet is in the post below.