Favourite servers would fall under the umbrella of what RTB does (community services, effectively) but as mentioned before, it's very hard to implement something along these lines. In most games, there are dedicated servers with static IPs (presumably they pay for this) and a static IP makes favouriting a server really easy.
However with Blockland, you're operating with two possible variables - either the IP or the player's name. Both of these can often be subject to regular change, especially the IP because not many ISPs will give their residential customers a static ip. Furthermore, Blockland servers tend to change their themes quite regularly so you may favourite a CityRP one day and come back in a week to find the only thing in your list is "Freebuild, first here gets admin" and you think "wtf?"
I will look into the possibility of server-created infomaniac tips though, it'd be a good way to extend his usefulness.