The thing is, the more communities are added, the longer it will take to update all of them. Right now there's over a 100 communities, and it takes a little over 7 minutes to update them all, and then it starts over again.
This isn't a problem right now, but it won't scale forever. At some point (probably sooner than later), it will probably mean having to remove the communities with the least subscribers.
Is your bot open source? Was thinking about spinning up a lemmy instance and I'd consider adding it to help spread the load, I'm sure there are other instances that'd join in too