Unfortunately we don't get a lot of choice in regards to upgrading the forum, if you leave it as an older version you risk being hacked as any security holes may become widely publicised on the dark web. I don't like doing it either as the database is very large and it takes a few of days planning & testing to do.
This version of the forum is probably the most configurable for both user & admin, and also works on mobile phones, which until this version it didn't very well. Most of our traffic is via mobile these days.
It was my fault the search wasn't working well, as I wasn't aware of the option to disallow certain member groups being searched. It is now turned on so much easier to find a member.
If you ever come across anything you think should work and doesn't, then please let me know & I'll look into it.
Sorry for any inconvenience.