I'm a little bummed because one I posted today has the wrong date... the wrong year!! How did I miss that? Anyway... I'm trying to think of creative ways to fix it.
Great layouts! I like your non-cluttered style!
What I would suggest for your date mistake:
Print (or stamp) the proper date on another piece of cardstock (maybe a nice brown or something complimentary for your layout) and then cut it out and glue it on top of your original date. It would look similar to your title page dates and titles.
I did this once too, I wrote FULL instead of FILL, so I printed the proper word on dark brown cardstock and glued it on top. I also did that for 2 other words so that it kinda looks like I did it on purpose for design effect LOL. It doesn't look great, but I really didn't feel like redoing the whole thing!