I went form 50 down to 75 down and I noticed that pages are actually loading slower and things in general seem more clunky and not as smooth as they did when i had 50 down. I did a speed test and it shows well over 80 down.
I suspect what you're seeing is one of the varagries of the Internet, unrelated to your speed change.
What you might try to improve performance is run DNSBench from GRC:
See if you're using the best DNS server for your location.
And if you're not already, you might try an ad blocker like Adguard or Adblock Plus. These days many (maybe most) web pages are so loaded with ads it takes those pages longer to load than it should.
I noticed the same issue. Upgraded from 50/50 to 75/75 and pages were immediately a LOT slower to load after the upgrade. Verizon speed tests show fast speeds, but it feels much slower.