Moving from old to new save - worth it?

I do this often because for whatever reason, after my legacy gets to about 5th or 6th gen weird glitches start happening in the save (probably due to me being close to maxing out my number of Sims by then since I tend to have large extended families), not always game breaking, but just annoying enough so I like to start fresh, save my favorite families to the gallery and plunk them into a new save and continue the legacy from there. 

A new save also gives me the chance to redo the towns, add different lots for entertainment, or maybe build up Newcrest with a different aesthetic or theme, because maybe I'm bored with what I had before, and also by this time all the OG townies in my game have died off so a new save brings them all back in case I wanted to have a story that involved them. 

The downside is that my saved Sims lose their family connections if they live in different households, but I was able to reconnect one set to another recently using the new "adopt" option (is this from R&L or base game? Not sure), so my elder Sim mother could basically claim back two of her adult children who lived in another household and put them back on her family tree. The separate families also have to get to know one another again, because the relationships are back to square one (I don't use cheats for things like that--I suppose you could maybe?), but given how long I've played the characters, most have pristine reputation or some other trait that makes friendships quick to build. Not an issue for me. 

It is tedious to recreate a lot of things, but also it feels like a fresh start with familiar characters and at least in my case, the game runs very smooth when starting fresh. No cobwebs in the files I guess. 😊Plus, as you mentioned, some bug fixes/updates only apply to new saves, so you get that benefit too.