I got another turn of Indy's spreadsheet if anyone is interested
Excellent work! I like a lot that you've done--you've cleaned up a lot of the things I had on my to-do list like simplifying the copy/paste work month to month, auto-referencing the mortgage sheet for equity, etc.
A couple of comments based off my experience with my version:
1) In the mortgage sheet, you auto-calculate the payoff balance, but I don't see any place where you take amortization into account. If I'm paying extra on the principle, doesn't that impact the principle to interest ratio on the remainder of the loan? Meaning, wouldn't I have a great proportion of principle in my next payments that is unaccounted for in the formula? This has been my experience, but perhaps I'm missing something. That's why I kept that sheet simple and didn't try to auto-calculate the balance. Instead I just check my balance (by phoning the bank) once per month and update it.
2) Nice catch on the second paycheck deduction table. Clearly I am a one income household. :)
3) I like your shortened months on the tabs.
4) Years to FI is a great stat!
5) YTD total savings is great too.
These are all really good tweaks to the sheet. I'm wondering if many of them don't belong in the master copy in some form of merge.