This finale proved that the show should have ended after Season 2 (when the Ted/Robin thing would have made sense) and Barney deserved a spin-off for seven years. But, since we have what we have, in the least, the writers should have ended the finale with Ted/mother at the Farhampton train station jointly holding the umbrella and playfully debating the meaning of the "T.M." The addition of the final scene shit on dear old mom and Ted's five (?) year marriage. And, to think, it was all planned from the beginning as proven by the kids' final dialogue. Fuck that.
If this episode had any redeeming value, it was through Barney's vignettes. From the "Playbook II - Electric Bang-A-Loo" (yes, that was its subtitle), to Jim Nance's "Sorry, bro", to Barney's comment of age 40 being the prime years for hooking up with twenty-somethings because he doesn't need to be emotionally distant to remind girls with daddy issues of their messed up dads, but because he freaking looks like their dads, to finding the girl to whom he pledges his love, Barney had the best finale for a character on this show. And the subsequent slut-shaming in McLaren's was a humorous touch.
In the end, for me, everything after Season 4 was hit or miss, but I watched it regularly anyway. My mistake.
Oh, and calling it now, "Number 31" will be the protagonist in How I Met Your Dad. See you in nine years, thread.