add new blocklists and remove old ones that are no longer current or maintained.

To expand on this, I think it needs to be acted on as I e.g. see there is entries in the default ad tracker list e.g. blocking cookielaw which breaks a fair few sites, using that list I also couldnt pay for games on the xbox store.  There is abandoned disconnect lists on there which to be frank makes nextdns look like a unmaintained project, and you are missing several higher quality lists.

The ultimate solution is to add the ability for people to add their own blacklists, it removes the headache from nextdns in needing to check if lists are still relevant etc, but if you cant do this, then you should be adding everything that is requested and still being maintained.  At least do some housekeeping.