I've been using opis with it's mapwriter map for awhile now and I rarely if ever experience any issues with it. Beyond the need to manually delete it's map folder when ever I need to regenerate the world for my server. As for the way points, I've never had any issue with it forgetting them. However I do use both opis and journey map together, with opis serving as my mini map and journey map for the in world way points and full screen map. I also mirror all my important way points between both maps as I like to use them side by side.
Now as for journey maps, its not that bad on resources if you go into it's options and make sure the webmap is always disabled. Other wise it will load a small webserver a long with minecraft to allow for you to view the map in your web browser and naturally take up good a bit of resources in the process.
I think it has to do with FTB swapping over to the curseforge launcher once it is ready and abandoning their own launcher. Which is something that's been going on for awhile now, ever since the FTB/Curse deal and people are worrying about FTB's fate.