I have a google sheet for my mortgage payoff. It has the original amortization table on the left, and my "actual" on the right. Every month, when we pay a little more, I get to delete a payment at the end of the actual. Very rewarding.
We also 'strategically' had PMI (paid it off in a year and 1 month). Then we went from there and are still paying the $81.84 per month that we would have paid to PMI to the mortgage, so even if we have a tighter month, then we will put money towards that.
As to the retirement funds vs. house, we like to spread it around. 12k in the 401k this year, moving as much as possible from any raises into my wife's 457b (no early withdrawal penalty), and then some in the house. I know it's not necessarily the best from an optimization perspective (4.25% mortgage), but I have never talked to someone who paid off their mortgage who regretted it. Just the peace of mind alone seems well worth it.